explain xkcd - User contributions [en]

2641: Mouse Turbines

2022-07-05T13:27:11Z

172.70.110.121: Assuming that electricity needs are proportional to body mass seems dubious :-)

{{comic
| number = 2641
| date = July 4, 2022
| title = Mouse Turbines
| image = mouse_turbines.png
| titletext = It's sad seeing those videos of turbine blade being torn apart in high winds, but it's the only way they can disperse their seeds.
}}

==Explanation==
{{incomplete|Created by a RENEWABLE ENERGY RODENT - Elaborate on the title text. Do NOT delete this tag too soon.}}

[[Beret Guy]] and [[Megan]] are walking during the summer, where Beret Guy expresses his appreciation for typical features of a summer day. He also mentions "wind turbines" put up by field mice, which Megan initially assumes to be referring to {{w|Taraxacum|dandelions}} (similar to the wordplay that Beret Guy utilized in [[1322: Winter]].) However, Beret Guy turns out to be speaking literally, as he picks up what is in fact a tiny {{w|wind turbine}}, says to [https://www.dandelionpress.com/dandelion-blog/2015/4/6/how-to-wish-on-a-dandelion make a wish,] and blows into it. This causes the blades of the turbine to spin rapidly, generating a lot of power for the structure it is connected to, thus causing a field mouse to cheer in excitement.

Sadly, the power output per size of wind turbines increases with their size,[https://www.energy.gov/eere/articles/wind-turbines-bigger-better] a limitation not shared by other forms of renewable energy such as {{w|solar panel}}s and {{w|pico hydro}}. According to [https://www.omnicalculator.com/ecology/wind-turbine this calculator], a 10 centimeter radius wind turbine powered by a 5.7 meter/second breath[https://www.sciencedirect.com/science/article/pii/S2215098616300830] would produce one watt at just 26% efficiency.

Further frustrating mouse use of wind power, {{w|Wind gradient|windspeed increases logarithmically with height}} above ground. Windspeed is reported as its value 10 meters above ground, where it is 1.5 times faster than at ground level.[https://www.nooutage.com/wind.htm] In the U.S., where Randall lives, average year-round windspeed is about 15 km/h,[https://sciencing.com/average-daily-wind-speed-24011.html] or about 2.8 m/s at ground level, yielding only 0.11 watts from such turbines. However, a typical adult mouse weighs 25 grams,[https://web.jhu.edu/animalcare/procedures/mouse.html] compared to about 81 kilograms for humans in the U.S.,[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3408371/] so presumably mouse electricity needs would be about 0.03% of people's.{{Dubious}} The average U.S. residential customer uses 1,242 watts of electricity,[https://www.electricchoice.com/blog/electricity-on-average-do-homes/] 0.03% of which is 0.37 watts. Therefore, three such turbines could be able to serve about 89% of a mouse's needs. While this figure does not account for necessary {{w|home energy storage}} efficiency (92.5% for the {{w|Tesla Powerwall}}) overhead, mice usually live much less extravagantly than typical Americans,{{citation needed}} so three turbines per mouse should be sufficient.

The title text builds on the similarities between small wind turbines and dandelions by claiming that turbines reproduce by dispersing their blades, in the manner of dandelion {{w|seed dispersal}}. Randall's suggestion of turbine seeds conflicts with Beret Guy's assertion that the turbines were built by field mice.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Megan and Beret Guy are walking on grass.]
:Beret Guy: Ahh, summer!
:Beret Guy: The clouds are big, the bugs are zooming,

:[Beret Guy stops walking. There are three small trefoil structures and a tiny building on the grass in front of him.]
:Beret Guy: and the field mice have put up their little wind turbines.

:[Beret Guy picks up one of the turbines. Under the turbine there is a wire attached to the ground.]
:Megan (off-panel): You mean dandelions?
:Beret Guy: No.

:[Beret Guy holds the turbine in front of him.]
:Beret Guy: Make a wish!

:[Beret Guy blows into the turbine blades and makes them spin. The wire transfers electricity towards the ground.]
:''Puff''
:⚡ ⚡ ⚡ ⚡
:Voice at ground level: Yaaay!

{{comic discussion}}

[[Category:Comics featuring Megan]]
[[Category:Comics featuring Beret Guy]]
[[Category:Animals]]

2637: Roman Numerals

2022-06-27T17:26:18Z

172.70.110.121: rearranged the intro sentences that explain the name of Arabic/Hindu-Arabic numerals, to be less awkward

{{comic
| number = 2637
| date = June 24, 2022
| title = Roman Numerals
| image = roman_numerals.png
| titletext = 100he100k out th1s 1nno5at4e str1ng en100o501ng 15e been 500e5e50op1ng! 1t's 6rtua100y perfe100t! ...hang on, what's a "virtuacy"?
}}

==Explanation==
{{incomplete|100reate500 by a LXXXT  - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

Roman numerals are the system of representing numbers used during the Roman Empire. The letters I, V, X, L, C, D, and M are used to represent numbers, with each letter representing a consistent value. Specifically, I represents 1, V represents 5, X represents 10, L represents 50, C represents 100, D represents 500, and M represents 1000. One way of stating the rules for combining Roman numerals next to each other are that a Roman numeral is added to a Roman numeral of equal or lesser value just to its right (e.g., II=1+1=2 because 1≥1, and VI=5+1=6 because 5≥1), and a Roman number is subtracted from a Roman numeral of greater value just to its right (e.g., IV=5-1=4 because 1<5, and IX=10-1=9 because 1<10). (Also, each place must be written separately, e.g., one cannot represent 49 via IL but instead must represent the tens place and ones place separately via XL IX—although the space would not be included in practice).

The modern system of representing numbers is a decimal positional notation using the numerals (0, 1, 2, 3, 4, 5, 6, 7, 8, and 9). Westerners often call this system "Arabic numerals" or "Hindu–Arabic numerals" because they were invented in India and introduced to Europe by Arabic merchants. Instead of concatenating several 1s, the single character 2 represents 1+1, 3 represents 1+1+1, etc… all the way to 9 representing 1+1+1+1+1+1+1+1+1. Integers larger than nine are represented as a sum of digits multiplied by different powers of ten. Each time a digit is moved one place to the left, the value that it represents is multiplied by ten (e.g., moving 3 to the left, starting in the ones place, changes the value that it represents from three to three tens to three hundreds to three thousands…). Positional notations require a character for the additive identity, 0, to fill in any gaps so that the digits to its left are positioned correctly. The string "4096" represents 4×103+0×102+9×101+6×100.

Thus in Roman numerals a digit always has the same absolute value but may be treated as positive or negative depending on the digit after it, whereas for Hindu-Arabic numerals, a digit's value changes by a power of 10 depending on its absolute position and is never subtracted.

Cueball's original equations in Roman Numeral form are:
<center>I + I = II</center>
<center>II + II = IV</center>
<center>IV + V = IX</center>

Translated normally into more familiar Hindu–Arabic numerals, these equations are:
<center>1 + 1 = 2</center>
<center>2 + 2 = 4</center>
<center>4 + 5 = 9</center>

But Randall/Cueball replaced each letter individually with its value in Hindu-Arabic numerals — ignoring the abovementioned rules for interpreting combined Roman numbers, instead using the rules of Roman Numerals. "I" is replaced with "1", "V" is replaced with "5", and "X" is replaced with "10". For example, for IX at the end of the last equation, "I" is replaced with "1", and "X" is replaced with "10", so "IX" becomes "110". Thus, the equations are written
<center>1 + 1 = 1 1</center>
<center>1 1 + 1 1 = 1 5</center>
<center>1 5 + 5 = 1 10</center>
where the spaces have been added for clarity.

The joke is that because Arabic numerals do not use the same rules of addition and subtraction as Roman numerals, the equations appear incorrect in both systems. The usual interpetation of 11 is 10+1, not 1+1 as it is under the rules for interpreting Roman numerals. Randall derives additional humor from the premise that Cueball seems to know Roman numerals better than Arabic numerals (as demonstrated by the fact that he translated only the symbology and not the grammar) so that he would do math in Roman numerals and have to remember to convert his equations to Arabic numerals at the end. Schoolchildren in the West have been taught to do math with Arabic numerals, not Roman numerals, for centuries.

In the title text, Randall applies the same idea of replacing Roman numerals with their values in Arabic numerals to strings of English words.

{| style="border:1px solid #ccd;"
|- style="text-align:center;"
| style="background-color:#ccd;" | 100
| he
| style="background-color:#ccd;" | 100
| k
| out
| th
| style="background-color:#ccd;" | 1
| s
|
| style="background-color:#ccd;" | 1
| nno
| style="background-color:#ccd;" | 5
| at
| style="background-color:#ccd;" | 4
| e
| str
| style="background-color:#ccd;" | 1
| ng
| en
| style="background-color:#ccd;" | 100
| o
| style="background-color:#ccd;" | 501
| ng
|
| style="background-color:#ccd;" | 15
| e
| been
|
| style="background-color:#ccd;" | 500
| e
| style="background-color:#ccd;" | 5
| e
| style="background-color:#ccd;" | 50
| op
| style="background-color:#ccd;" | 1
| ng!
|
| style="background-color:#ccd;" | 1
| t's
|
| style="background-color:#ccd;" | 6
| rtua
| style="background-color:#ccd;" | 100
| y
| perfe
| style="background-color:#ccd;" | 100
| t!
|- style="text-align:center;"
| style="background-color:#ccd;" | C
| he
| style="background-color:#ccd;" | C
| k
| out
| th
| style="background-color:#ccd;" | I
| s
|
| style="background-color:#ccd;" | I
| nno
| style="background-color:#ccd;" | V
| at
| style="background-color:#ccd;" | IV
| e
| str
| style="background-color:#ccd;" | I
| ng
| en
| style="background-color:#ccd;" | C
| o
| style="background-color:#ccd;" | DI
| ng
|
| style="background-color:#ccd;" | IV
| e
| been
|
| style="background-color:#ccd;" | D
| e
| style="background-color:#ccd;" | V
| e
| style="background-color:#ccd;" | L
| op
| style="background-color:#ccd;" | I
| ng!
|
| style="background-color:#ccd;" | I
| t's
|
| style="background-color:#ccd;" | VI
| rtua
| style="background-color:#ccd;" | LL/C
| y
| perfe
| style="background-color:#ccd;" | C
| t!
|}

The original string (with letters that would be interpreted as Roman numerals capitalized) is, "CheCk out thIs InnoVatIVe strIng enCoDIng I'Ve been DeVeLopIng! It's VIrtuaLLy perfeCt!" For the first word, "Check," C is replaced with the value of that Roman numeral in Arabic numerals, i.e., "100", in both instances of the word, which results in "100he100k". Unlike in the comic, Randall combines Roman numbers using the proper rules of addition and subtraction. For example, he replaces "IV" with "4", not "15", e.g., "innovative" becomes "1nno5at4e", not "1nno5at15e". (However, "I've" becomes "15e", not "4e", presumably because the apostrophe was removed after, not before, replacing the Roman numerals with Arabic numerals. However, there is not an obvious reason why Randall removed the apostrophe.) However, there are problems with this. One example is that the double L in "virtually" is replaced with 100. This correctly remembers Roman numerals' rule of adding the value of a letter to the value of an equal-valued letter just to its right, but in Roman numerals, a single number should never have multiple Vs, multiple Ls, or multiple Ds, e.g., 100 should be represented by C, not LL. This would mean that a simplistic decoding script would erroneously decode "6rtua100y" to "virtuacy", not "virtually". Thus, this string encoding system is not actually perfect. (Until the modern codification in general use today, Roman numerals weren't standardised that much, so "LL" could have been a tolerated alternative to "C". For more on that, see {{w|Roman_numerals#Classical_Roman_numerals}}. However, having the decoding script use that would not solve the problem but instead would make the decoding script replace Cs with LLs instead, e.g., "delloding sllript".)

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Cueball writing on a wall or a whiteboard.]
:1+1=11
:11+11=15
:15+5=110

:[Caption below the panel:]
:Remember, Roman numerals are archaic, so always replace them with modern ones when doing math.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Math]]

Talk:2637: Roman Numerals

2022-06-25T00:37:54Z

172.70.110.121:

Immediately came to this site as soon as the comic popped up [[Special:Contributions/172.70.114.43|172.70.114.43]] 22:43, 24 June 2022 (UTC)

For anyone wondering about the alt text: "CheCk out thIs InnoVatIVe strIng enCoDIng IVe been DeVeLopIng! It's VIrtuaCy perfeCt! ...hang on, what's a "virtuacy"?" Roman numerals are in uppercase. : [[Special:Contributions/162.158.90.209|162.158.90.209]] 23:00, 24 June 2022 (UTC)
:I didn't see this comment, but I decoded it above. Feel free to update with your text, which includes the casing.
::It should be virtually - LL is 50 50, C is 100. [[Special:Contributions/172.70.110.121|172.70.110.121]] 00:37, 25 June 2022 (UTC)

Relevant OEIS entry: https://oeis.org/A093788 [[Special:Contributions/162.158.129.117|162.158.129.117]] 23:43, 24 June 2022 (UTC)

2636: What If? 2 Countdown

2022-06-23T20:54:43Z

172.70.110.121:

{{comic
| number = 2636
| date = June 22, 2022
| title = What If? 2 Countdown
| image = what_if_2_countdown.png
| titletext = If you don't end the 99 Bottles of Beer recursion at N=0 it just becomes The Other Song That Never Ends.
}}

==Explanation==
{{incomplete|Created by FOUR SCORE AND 7 BOTTLES OF BEER ON THE WALL - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic takes the idea of {{w|Advent calendar}}s, and takes it to the extreme. It uses rather absurd and/or obscure ways to measure the amount of time until [[Randall]]'s new book ''What if? 2'' is released, with esoteric units or esoteric numbers. And often both.

Some concepts that appear several times throughout the calendar are:

* '''{{w|SI prefixes}}''', which can be applied to the beginning of a unit's name to multiply or divide the unit by powers of 10 or 1,000. This is standard for units like meters and grams, but is rarely applied to measurements of time.
* The '''{{w|Gettysburg Address}}''', a famous speech delivered by U.S. president Abraham Lincoln in 1863, where he began by referring to the signing of the Declaration of Independence taking place "four score and seven years ago". A score is a dated term for the number 20, so "four score and seven" is equivalent to 87.
* A '''dog year''' is traditionally considered to be one-seventh the length of a normal human year, since a dog's overall lifespan is roughly one-seventh of a typical human's. The comic applies this to other units of time, such as minutes and months, each of which is also one-seventh the length of the standard unit.
* Other comparative durations of time that are not normally or usefully applied to day-length multiples. At the top end, there is the age of the universe, at the other there is {{w|Planck_units#Planck_time|Planck-time}} – with entire durations of periods of human history and the time needed to watch popular TV/film franchises in-between – most of which require a non-trivial multiplier or divisor to bring them to the necessary scale required.
* A '''{{w|baker's dozen}}''' is 13, or one more than a normal dozen. Here, the "baker's" prefix can be applied to any unit by adding an extra one of its constituent parts, like an extra hour added to a day.
* '''{{w|Irrational numbers}}''' like {{w|pi}} (3.14159...), {{w|Euler's number}} or ''e'' (2.71828...), the {{w|golden ratio}} (1.61803...), and the {{w|square root of 2}} (1.41421...). These are all interesting numbers because of their mathematical properties, but very impractical to use as arbitrary measurements of time because they have an endless series of non-repeating decimal digits.
* The teenage dating game {{w|Seven minutes in heaven}}.
* Rotation and revolution periods of various planets and moons in the Solar System.

{| class="wikitable"
|-
! Days !! Date !! Units !! Exact value !! Explanation
|-
| 83 || Jun 22 || πe millidecades || 82.0304 days || π =~ 3.14159, e =~ 2.718, so πe is about 22.459. A millidecade is 1/1000 decade, or 1/100 year, or about 3.6525 days. Multiplying these results in 82.03 days. This is a play on Euler's identity, eiπ=-1, but raising pi to the power of e instead.
|-
| 82 || Jun 23 || 7 megaseconds || 81.0185 days || 7,000,000 seconds
|-
| 81 || Jun 24 || e lunar months || 80.27247 days || A lunar month =~ 29.53059 days, e =~ 2.718
|-
| 80 || Jun 25 || 60 rotations of Foucault's pendulum in Paris || 79.67 days || Foucault's pendulum rotates once every 31.8 hours because of the rotation of the Earth and its latitude.
|-
| 79 || Jun 26 || 8 milligenerations || 78.89 days || A generation is in general 22-33 years, with a mean of 27; so 8 * 0.001 (milli) * 365.2425 (accounting for leap years) * 27 =~ 78.89 days
|-
| 78 || Jun 27 || 777,777 dog minutes || 77.16 days || A popular myth is that dogs age 7 times faster than humans, so 1 dog minute equals 1/7 human minutes.
|-
| 77 || Jun 28 || 7! episodes of ''Jeopardy!'' (skipping ads) || 77 days || 7!=7*6*5*4*3*2*1=5040 - The standard episode of ''Jeopardy'' is 22-26 minutes skipping ads - taking the lowest value you get 110880 minutes total, which is the exact value needed.
|-
| 76 || Jun 29 || 5,000 repeats of ''99 Bottles of Beer'' || 76.3889 days || Each verse of {{w|99 Bottles of Beer}} is "''N'' bottles of beer on the wall, ''N'' bottles of beer. Take one down, pass it around, ''N-1'' bottles of beer on the wall." The entire song contains 99 verses. Randall apparently sings this rather slowly at around 72 bpm, taking about 13 seconds per verse.
|-
| 75 || Jun 30 || 5 baker's fortnights (15 days) || 75 days || A {{w|baker's dozen}} is a dozen (12) plus 1 extra item. Randall has generalized this to adding 1 to any unit. A fortnight is 2 weeks, so a baker's fortnight is 15 days. 5x15 is 75 days.
|-
| 74 || Jul 1 || √2 dog years || 73.79 days || See day 78 (Jun 27)
|-
| 73 || Jul 2 || π millivics (1/1000th of Queen Victoria's reign) || 72.966631 days || Queen Victoria ruled between 20 June 1837 and 22 January 1901 (23,226 days).
|-
| 72 || Jul 3 || 42 drives from NYC to LA (Google Maps estimate) || 71.75 days || According to Google Maps, the drive from New York City to Los Angeles via I-80 W (2789 miles or 4489 km) takes 41 hours.
|-
| 71 || Jul 4 || 1,000 viewings of ''Groundhog Day''|| 70.14 days|| Using 101-minute run time.
|-
| 70 || Jul 5 || 100,000 minutes || 69.44 days||
|-
| 69 || Jul 6 || 1/10th of Martian year || 68.70 Earth days || Martian sidereal and tropical years both round to 687.0 Earth days
|-
| 68 || Jul 7 || 1,234,567 sound-miles || 67.63 days || The speed of sound in air depends on the temperature. 15 °C or 59 °F gives the value 340 m/s and the travel time of 67.6349058 days.
|-
| 67 || Jul 8 || 2^π^e seconds ||5,766,073 seconds = 66.7 days || 2^(π^e)
|-
| 66 || Jul 9 || 2^16 beats (Swatch Internet Time) || 65.536 days || {{w|.beat}} is equal to 1/1000 day.
|-
| 65 || Jul 10 || 1,000 ISS orbits || 64.58 days || Each orbit of the ISS takes 90-93 minutes. Here a value of 93 minutes is used.
|-
| 64 || Jul 11 || Five hundred twenty five thousand (base seven) minutes|| 62.8833333333333 days || This refers to {{w|radix}}-7 arithmetic: 525,0007 minutes = 90,55210 minutes. Also references the opening and recurring line "Five hundred twenty five thousand six hundred minutes" from {{w|Seasons of Love}}, a song from the musical {{w|Rent (musical)|''Rent''}}, which is also referenced in [[1047: Approximations]]. "base seven" also has the same rhythm as "six hundred".
|-
| 63 || Jul 12 || 10^50 Planck times || 62.38 days || 10^50 x 5.39 x 10^-44 seconds
|-
| 62 || Jul 13 || 4,000 episodes of ''The Office'' (skipping ads)|| 62.5 days || {{w|The Office (British TV series)|''The Office''}} was originally a {{w|BBC}} television show which had no commercial breaks, but Randall is obviously more familiar with the {{w|The_Office_(American_TV_series)|US version}}. This US "half-hour" comedy format contains 22.5 minutes of content (including the title sequence) and 7.5 minutes of ads. 
|-
| 61 || Jul 14 || four score and seven kilominutes || 60.4166 days || 87 * 1000 minutes
|-
| 60 || Jul 15 || 2 lunar months || 59.06 days || There are a number of different ways to define the {{w|lunar month}}. The most common is the synodic month, because it relates to the phases of the moon, and it's approximately 29.53 days.
|-
| 59 || Jul 16 || half a day on Venus || 58.375 days || A Venus synodic day is 116 days 18 hours.
|-
| 58 || Jul 17 || 5 megaseconds || 57.8704 days || 5,000,000 seconds
|-
| 57 || Jul 18 || 30 microLits (1/1,000,000th of the time since the invention of literature) || 4681-4763 years x 10^-6 || Randall is stating that "literature" was invented approximately 2700 BCE. This is consistent with the earliest surviving coherent Sumerian texts, but the earliest proto-writing likely developed at least 500 years earlier according to {{w|History of writing}}.
|-
| 56 || Jul 19 || 1,000 viewings of ''Run Lola Run'' || 55.556 days || Using a run time of 80 minutes.
|-
| 55 || Jul 20 || one million sound-miles || 54.78 days || The speed of sound in air depends on the temperature. 15 °C or 59 °F gives the value 340 m/s and the travel time of 54.7843137 days.
|-
| 54 || Jul 21 || 30 Ionian months || 53.0741 days || Orbital period of Io around Jupiter is approximately 1.77 days.
|-
| 53 || Jul 22 || one dog year || 52.18 days || See day 78 (Jun 27)
|-
| 52 || Jul 23 || 60 viewings of ''Star Wars Episodes I-IX'' || 51.75 days || According to [https://dorksideoftheforce.com/2021/05/04/how-long-to-watch-every-star-wars-movie/ Fansided] the combined running times are 20 hours 42 minutes.
|-
| 51 || Jul 24 || 1/ 100,000,000,000th of the universe's age || 50.4035 days || The universe is estimated to be about 13.8 billion years old.
|-
| 50 || Jul 25 || 5 milli-generations || 49.3 days || See day 79 (Jun 26)
|-
| 49 || Jul 26 || 10,000 games of ''7 minutes in Heaven'' or 7 games of ''10,000 minutes in Heaven'' || 48.61 days || {{w|Seven minutes in heaven}} is a teenage make-out game lasting seven minutes. 10,000 minutes in Heaven is almost a week of making out.
|-
| 48 || Jul 27 || φ^e^π minutes || 47.6164 days || 68,567.57 minutes
|-
| 47 || Jul 28 || 4 megaseconds || 46.2963 days || 4,000,000 seconds
|-
| 46 || Jul 29 || 2^16 minutes || 45.5111 days || 65,536 minutes
|-
| 45 || Jul 30 || e^e^e seconds || 44.1467 days || 3,814,279.10 seconds
|-
| 44 || Jul 31 || π fortnights|| 43.98 days || 3.14159 * 14 days
|-
| 43 || Aug 1 || one devil's spacewalk (666 orbits of the ISS) || 43.01 days || See day 65 (Jul 10). 666 is the {{w|number of the beast}}.
|-
| 42 || Aug 2 || 1 kilowatt-hour per watt || 41.66 days || 1000 hours
|-
| 41 || Aug 3 || e^π Ionian months || 40.9390 days || Orbital period of Io around Jupiter is 1.769137786 days
|-
| 40 || Aug 4 || 30 rotations of Foucault's pendulum in Paris || 39.8357 days || Refer to Day 80 (Jun 25)
|-
| 39 || Aug 5 || e fortnights || 38.0559 days ||2.71828 * 14 days
|-
| 38 || Aug 6 || π^π baker's days (25 hours) || 37.98 days || See day 75 (Jun 30)
|-
| 37 || Aug 7 || one deciyear || 36.525 days || One tenth of one year
|-
| 36 || Aug 8 || 7! milliweeks || 35.28 days || 5040 × 0.001 weeks
|-
| 35 || Aug 9 || 100,000 plays of the ''Jeopardy!'' "Think" music || 34.72 days || ''Think'' is the music played while the contestants try to answer the Final Jeopardy question; it is 30 seconds long.
|-
| 34 || Aug 10 || 1000 basketball games (game time) || 33.33 days || Uses the NBA game time of four 12-minute quarters, or 48 minutes
|-
| 33 || Aug 11 || 777 hours || 32.375 days ||
|-
| 32 || Aug 12 ||one millilincoln (1/1000 of fourscore and seven years) || 31.78 days || {{w|Abraham Lincoln}}'s {{w|Gettysburg Address}} begins with the famous phrase "Four score and seven years ago". 1 score = 20 years
|-
| 31 || Aug 13 || 1,000 episodes of ''60 Minutes'' (skipping ads) || 31.25 days || Uses a television 'hour' containing 45 minutes of content and 15 minutes of ads
|-
| 30 || Aug 14 || all of ''Star Trek'', consecutively || ||
|-
| 29 || Aug 15 || 777,777 nanocenturies || 28.4077 days || 777,777 × 10-9 × 100 years
|-
| 28 || Aug 16 || one sidereal lunar month || 27.3 days || The time it takes moon to return to the same position relative to the fixed stars
|-
| 27 || Aug 17 || 6 dog months || 26.1 days || See day 78 (Jun 27)
|-
| 26 || Aug 18 || π^π kilominutes || 25.3209 days || 36,462.16 minutes
|-
| 25 || Aug 19 || 7 games of 7! minutes in Heaven || 24.5 days || 7 x 5040 (7 {{w|Factorial}}) minutes. See also day 49 (Jul 26).
|-
| 24 || Aug 20 || 50 viewings of the extended ''Lord of the Rings'' trilogy || ||
|-
| 23 || Aug 21 || a drive from NYC to LA where you keep remembering new things you forgot and have to go back 6 times || 22.21 days || See day 72 (Jul 3). This is for 6 round-trips and 1 one-way trip.
|-
| 22 || Aug 22 || ''It's a Small World'' sung at 1/10,000th speed || || {{w|It's a Small World}} is a song that was composed for the attraction of the same name at various {{w|Disney}} theme parks, and plays continuously at them in various languages.
|-
| 21 || Aug 23 || 500 hours || 20.8333 days ||
|-
| 20 || Aug 24 || √2 fortnights || 19.7990 days || 1.4142 × 14 days
|-
| 19 || Aug 25 || time it would take Vanessa Carlton to walk 1,000 miles || 18.94 days || {{w|Vanessa Carlton}} is an American singer, and {{w|A Thousand Miles}} is her most successful song. Randall estimates her walking speed at about 2.2 miles/hour.
|-
| 18 || Aug 26 || 100,000 breaths || .26 min/breath || Normal respiratory rate for adults is typically 12-20 breaths per minute. Randall may have a health problem or be a practitioner of "slow breathing".
|-
| 17 || Aug 27 || √2 megaseconds || 16.3682 days || 1.4142 × 1,000,000 seconds
|-
| 16 || Aug 28 || π^π^π πcoseconds || 15.5112 days || 1.3402 × 1018 picoseconds (i.e., 10-12 seconds), making a joke how π is written as "pi"
|-
| 15 || Aug 29 || one baker's fortnight (15 days) || 15 days || See day 75 (Jun 30)
|-
| 14 || Aug 30 || one baker's dozen (13) baker's days (25 hours) || 13.5416 days || 325 hours; see day 75 (Jun 30)
|-
| 13 || Aug 31 || 300 hours || 12.5 days ||
|-
| 12 || Sep 1 || one million seconds || 11.57 days ||
|-
| 11 || Sep 2 || one nonstop bike ride from NYC to LA || 10.54 days || Google maps estimates the trip at 253 hours
|-
| 10 || Sep 3 || 1/1,000th of a generation || 9.86 days || See day 79 (Jun 26)
|-
| 9 || Sep 4 || 777,777 seconds || 9.002 days ||
|-
| 8 || Sep 5 || 100 viewings of ''Groundhog Day'' || 7.014 days || Based on a running time of 101 minutes
|-
| 7 || Sep 6 || 100 games of ''Lincoln Kissing'' (Fourscore and seven minutes in Heaven) || 6.04 days || 8,700 minutes
|-
| 6 || Sep 7 || one pico-universe-lifetime || 5.04 days || See Day 51 (Jul 24)
|-
| 5 || Sep 8 || the ''Baby Shark'' chorus for a family of 50,000 sharks || ||
|-
| 4 || Sep 9 || one centiyear || 3.6525 days || 365.25 days * 1/100
|-
| 3 || Sep 10 || Cyndi Lauper's ''Time After Time'' played 1,000 times || 2.79 days || Based on a length of 4 minutes, 1 second
|-
| 2 || Sep 11 || ''Speed'' (1994) played at one frame per second || 1.933 days || {{w|Speed_(1994_film)}} has runtime of 116 minutes = 6,960 seconds = 167,040 film frames at standard frame rate of 24 frames/second
|-
| 1 || Sep 12 || F(99) where F(N) means sing all the verses of ''N Bottles of Beer On the wall'' followed by F(N-1) || 0.7639 days || Each iteration contains ''N'' verses. ''N + N-1 + N-2 ... + 1'' equals ''N * (N+1) / 2'', so 99 recursions = 4950 verses. Using the same 13-second (72 bpm) rate as Jun 29, this is close to 18 hours. Probably refers to Donald Knuth's article {{w|The Complexity of Songs}}.
|-
| 0 || Sep 13 || ''What If? 2'' release day || ||
|}

The title text refers to the recursive time period on Sep 12. If you don't stop when you reach N=0 bottles, the repetition never ends, so that time interval beecomes infinite. He likens it to {{w|The Song That Never Ends}}, another repetitive children's song, which is specifically intended to go on forever. The difference is that the Beer song has a natural stopping point at 0, while ''The Song That Never Ends'' is completely repetitive.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}

2636: What If? 2 Countdown

2022-06-23T20:50:57Z

172.70.110.121: /* Explanation */

{{comic
| number = 2636
| date = June 22, 2022
| title = What If? 2 Countdown
| image = what_if_2_countdown.png
| titletext = If you don't end the 99 Bottles of Beer recursion at N=0 it just becomes The Other Song That Never Ends.
}}

==Explanation==
{{incomplete|Created by LINCOLN KISSING - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic takes the idea of {{w|Among Us}}s, and takes it to the extreme. It uses rather absurd and/or obscure ways to measure the amount of time until [[Randall]]'s new book ''What if? 2'' is released, with esoteric units or esoteric numbers. And often both.

Some concepts that appear several times throughout the calendar are:

* '''{{w|SI prefixes}}''', which can be applied to the beginning of a unit's name to multiply or divide the unit by powers of 10 or 1,000. This is standard for units like meters and grams, but is rarely applied to measurements of time.
* The '''{{w|Gettysburg Address}}''', a famous speech delivered by U.S. president Abraham Lincoln in 1863, where he began by referring to the signing of the Declaration of Independence taking place "four score and seven years ago". A score is a dated term for the number 20, so "four score and seven" is equivalent to 87.
* A '''dog year''' is traditionally considered to be one-seventh the length of a normal human year, since a dog's overall lifespan is roughly one-seventh of a typical human's. The comic applies this to other units of time, such as minutes and months, each of which is also one-seventh the length of the standard unit.
* Other comparative durations of time that are not normally or usefully applied to day-length multiples. At the top end, there is the age of the universe, at the other there is {{w|Planck_units#Planck_time|Planck-time}} – with entire durations of periods of human history and the time needed to watch popular TV/film franchises in-between – most of which require a non-trivial multiplier or divisor to bring them to the necessary scale required.
* A '''{{w|baker's dozen}}''' is 13, or one more than a normal dozen. Here, the "baker's" prefix can be applied to any unit by adding an extra one of its constituent parts, like an extra hour added to a day.
* '''{{w|Irrational numbers}}''' like {{w|pi}} (3.14159...), {{w|Euler's number}} or ''e'' (2.71828...), the {{w|golden ratio}} (1.61803...), and the {{w|square root of 2}} (1.41421...). These are all interesting numbers because of their mathematical properties, but very impractical to use as arbitrary measurements of time because they have an endless series of non-repeating decimal digits.
* The teenage dating game {{w|Seven minutes in heaven}}.
* Rotation and revolution periods of various planets and moons in the Solar System.

{| class="wikitable"
|-
! Days !! Date !! Units !! Exact value !! Explanation
|-
| 83 || Jun 22 || πe millidecades || 82.0304 days || π =~ 3.14159, e =~ 2.718, so πe is about 22.459. A millidecade is 1/1000 decade, or 1/100 year, or about 3.6525 days. Multiplying these results in 82.03 days. This is a play on Euler's identity, eiπ=-1, but raising pi to the power of e instead.
|-
| 82 || Jun 23 || 7 megaseconds || 81.0185 days || 7,000,000 seconds
|-
| 81 || Jun 24 || e lunar months || 80.27247 days || A lunar month =~ 29.53059 days, e =~ 2.718
|-
| 80 || Jun 25 || 60 rotations of Foucault's pendulum in Paris || 79.67 days || Foucault's pendulum rotates once every 31.8 hours because of the rotation of the Earth and its latitude.
|-
| 79 || Jun 26 || 8 milligenerations || 78.89 days || A generation is in general 22-33 years, with a mean of 27; so 8 * 0.001 (milli) * 365.2425 (accounting for leap years) * 27 =~ 78.89 days
|-
| 78 || Jun 27 || 777,777 dog minutes || 77.16 days || A popular myth is that dogs age 7 times faster than humans, so 1 dog minute equals 1/7 human minutes.
|-
| 77 || Jun 28 || 7! episodes of ''Jeopardy!'' (skipping ads) || 77 days || 7!=7*6*5*4*3*2*1=5040 - The standard episode of ''Jeopardy'' is 22-26 minutes skipping ads - taking the lowest value you get 110880 minutes total, which is the exact value needed.
|-
| 76 || Jun 29 || 5,000 repeats of ''99 Bottles of Beer'' || 76.3889 days || Each verse of {{w|99 Bottles of Beer}} is "''N'' bottles of beer on the wall, ''N'' bottles of beer. Take one down, pass it around, ''N-1'' bottles of beer on the wall." The entire song contains 99 verses. Randall apparently sings this rather slowly at around 72 bpm, taking about 13 seconds per verse.
|-
| 75 || Jun 30 || 5 baker's fortnights (15 days) || 75 days || A {{w|baker's dozen}} is a dozen (12) plus 1 extra item. Randall has generalized this to adding 1 to any unit. A fortnight is 2 weeks, so a baker's fortnight is 15 days. 5x15 is 75 days.
|-
| 74 || Jul 1 || √2 dog years || 73.79 days || See day 78 (Jun 27)
|-
| 73 || Jul 2 || π millivics (1/1000th of Queen Victoria's reign) || 72.966631 days || Queen Victoria ruled between 20 June 1837 and 22 January 1901 (23,226 days).
|-
| 72 || Jul 3 || 42 drives from NYC to LA (Google Maps estimate) || 71.75 days || According to Google Maps, the drive from New York City to Los Angeles via I-80 W (2789 miles or 4489 km) takes 41 hours.
|-
| 71 || Jul 4 || 1,000 viewings of ''Groundhog Day''|| 70.14 days|| Using 101-minute run time.
|-
| 70 || Jul 5 || 100,000 minutes || 69.44 days||
|-
| 69 || Jul 6 || 1/10th of Martian year || 68.70 Earth days || Martian sidereal and tropical years both round to 687.0 Earth days
|-
| 68 || Jul 7 || 1,234,567 sound-miles || 67.63 days || The speed of sound in air depends on the temperature. 15 °C or 59 °F gives the value 340 m/s and the travel time of 67.6349058 days.
|-
| 67 || Jul 8 || 2^π^e seconds ||5,766,073 seconds = 66.7 days || 2^(π^e)
|-
| 66 || Jul 9 || 2^16 beats (Swatch Internet Time) || 65.536 days || {{w|.beat}} is equal to 1/1000 day.
|-
| 65 || Jul 10 || 1,000 ISS orbits || 64.58 days || Each orbit of the ISS takes 90-93 minutes. Here a value of 93 minutes is used.
|-
| 64 || Jul 11 || Five hundred twenty five thousand (base seven) minutes|| 62.8833333333333 days || This refers to {{w|radix}}-7 arithmetic: 525,0007 minutes = 90,55210 minutes. Also references the opening and recurring line "Five hundred twenty five thousand six hundred minutes" from {{w|Seasons of Love}}, a song from the musical {{w|Rent (musical)|''Rent''}}, which is also referenced in [[1047: Approximations]]. "base seven" also has the same rhythm as "six hundred".
|-
| 63 || Jul 12 || 10^50 Planck times || 62.38 days || 10^50 x 5.39 x 10^-44 seconds
|-
| 62 || Jul 13 || 4,000 episodes of ''The Office'' (skipping ads)|| 62.5 days || {{w|The Office (British TV series)|''The Office''}} was originally a {{w|BBC}} television show which had no commercial breaks, but Randall is obviously more familiar with the {{w|The_Office_(American_TV_series)|US version}}. This US "half-hour" comedy format contains 22.5 minutes of content (including the title sequence) and 7.5 minutes of ads. 
|-
| 61 || Jul 14 || four score and seven kilominutes || 60.4166 days || 87 * 1000 minutes
|-
| 60 || Jul 15 || 2 lunar months || 59.06 days || There are a number of different ways to define the {{w|lunar month}}. The most common is the synodic month, because it relates to the phases of the moon, and it's approximately 29.53 days.
|-
| 59 || Jul 16 || half a day on Venus || 58.375 days || A Venus synodic day is 116 days 18 hours.
|-
| 58 || Jul 17 || 5 megaseconds || 57.8704 days || 5,000,000 seconds
|-
| 57 || Jul 18 || 30 microLits (1/1,000,000th of the time since the invention of literature) || 4681-4763 years x 10^-6 || Randall is stating that "literature" was invented approximately 2700 BCE. This is consistent with the earliest surviving coherent Sumerian texts, but the earliest proto-writing likely developed at least 500 years earlier according to {{w|History of writing}}.
|-
| 56 || Jul 19 || 1,000 viewings of ''Run Lola Run'' || 55.556 days || Using a run time of 80 minutes.
|-
| 55 || Jul 20 || one million sound-miles || 54.78 days || The speed of sound in air depends on the temperature. 15 °C or 59 °F gives the value 340 m/s and the travel time of 54.7843137 days.
|-
| 54 || Jul 21 || 30 Ionian months || 53.0741 days || Orbital period of Io around Jupiter is approximately 1.77 days.
|-
| 53 || Jul 22 || one dog year || 52.18 days || See day 78 (Jun 27)
|-
| 52 || Jul 23 || 60 viewings of ''Star Wars Episodes I-IX'' || 51.75 days || According to [https://dorksideoftheforce.com/2021/05/04/how-long-to-watch-every-star-wars-movie/ Fansided] the combined running times are 20 hours 42 minutes.
|-
| 51 || Jul 24 || 1/ 100,000,000,000th of the universe's age || 50.4035 days || The universe is estimated to be about 13.8 billion years old.
|-
| 50 || Jul 25 || 5 milli-generations || 49.3 days || See day 79 (Jun 26)
|-
| 49 || Jul 26 || 10,000 games of ''7 minutes in Heaven'' or 7 games of ''10,000 minutes in Heaven'' || 48.61 days || {{w|Seven minutes in heaven}} is a teenage make-out game lasting seven minutes. 10,000 minutes in Heaven is almost a week of making out.
|-
| 48 || Jul 27 || φ^e^π minutes || 47.6164 days || 68,567.57 minutes
|-
| 47 || Jul 28 || 4 megaseconds || 46.2963 days || 4,000,000 seconds
|-
| 46 || Jul 29 || 2^16 minutes || 45.5111 days || 65,536 minutes
|-
| 45 || Jul 30 || e^e^e seconds || 44.1467 days || 3,814,279.10 seconds
|-
| 44 || Jul 31 || π fortnights|| 43.98 days || 3.14159 * 14 days
|-
| 43 || Aug 1 || one devil's spacewalk (666 orbits of the ISS) || 43.01 days || See day 65 (Jul 10). 666 is the {{w|number of the beast}}.
|-
| 42 || Aug 2 || 1 kilowatt-hour per watt || 41.66 days || 1000 hours
|-
| 41 || Aug 3 || e^π Ionian months || 40.9390 days || Orbital period of Io around Jupiter is 1.769137786 days
|-
| 40 || Aug 4 || 30 rotations of Foucault's pendulum in Paris || 39.8357 days || Refer to Day 80 (Jun 25)
|-
| 39 || Aug 5 || e fortnights || 38.0559 days ||2.71828 * 14 days
|-
| 38 || Aug 6 || π^π baker's days (25 hours) || 37.98 days || See day 75 (Jun 30)
|-
| 37 || Aug 7 || one deciyear || 36.525 days || One tenth of one year
|-
| 36 || Aug 8 || 7! milliweeks || 35.28 days || 5040 × 0.001 weeks
|-
| 35 || Aug 9 || 100,000 plays of the ''Jeopardy!'' "Think" music || 34.72 days || ''Think'' is the music played while the contestants try to answer the Final Jeopardy question; it is 30 seconds long.
|-
| 34 || Aug 10 || 1000 basketball games (game time) || 33.33 days || Uses the NBA game time of four 12-minute quarters, or 48 minutes
|-
| 33 || Aug 11 || 777 hours || 32.375 days ||
|-
| 32 || Aug 12 ||one millilincoln (1/1000 of fourscore and seven years) || 31.78 days || {{w|Abraham Lincoln}}'s {{w|Gettysburg Address}} begins with the famous phrase "Four score and seven years ago". 1 score = 20 years
|-
| 31 || Aug 13 || 1,000 episodes of ''60 Minutes'' (skipping ads) || 31.25 days || Uses a television 'hour' containing 45 minutes of content and 15 minutes of ads
|-
| 30 || Aug 14 || all of ''Star Trek'', consecutively || ||
|-
| 29 || Aug 15 || 777,777 nanocenturies || 28.4077 days || 777,777 × 10-9 × 100 years
|-
| 28 || Aug 16 || one sidereal lunar month || 27.3 days || The time it takes moon to return to the same position relative to the fixed stars
|-
| 27 || Aug 17 || 6 dog months || 26.1 days || See day 78 (Jun 27)
|-
| 26 || Aug 18 || π^π kilominutes || 25.3209 days || 36,462.16 minutes
|-
| 25 || Aug 19 || 7 games of 7! minutes in Heaven || 24.5 days || 7 x 5040 (7 {{w|Factorial}}) minutes. See also day 49 (Jul 26).
|-
| 24 || Aug 20 || 50 viewings of the extended ''Lord of the Rings'' trilogy || ||
|-
| 23 || Aug 21 || a drive from NYC to LA where you keep remembering new things you forgot and have to go back 6 times || 22.21 days || See day 72 (Jul 3). This is for 6 round-trips and 1 one-way trip.
|-
| 22 || Aug 22 || ''It's a Small World'' sung at 1/10,000th speed || || {{w|It's a Small World}} is a song that was composed for the attraction of the same name at various {{w|Disney}} theme parks, and plays continuously at them in various languages.
|-
| 21 || Aug 23 || 500 hours || 20.8333 days ||
|-
| 20 || Aug 24 || √2 fortnights || 19.7990 days || 1.4142 × 14 days
|-
| 19 || Aug 25 || time it would take Vanessa Carlton to walk 1,000 miles || 18.94 days || {{w|Vanessa Carlton}} is an American singer, and {{w|A Thousand Miles}} is her most successful song. Randall estimates her walking speed at about 2.2 miles/hour.
|-
| 18 || Aug 26 || 100,000 breaths || .26 min/breath || Normal respiratory rate for adults is typically 12-20 breaths per minute. Randall may have a health problem or be a practitioner of "slow breathing".
|-
| 17 || Aug 27 || √2 megaseconds || 16.3682 days || 1.4142 × 1,000,000 seconds
|-
| 16 || Aug 28 || π^π^π πcoseconds || 15.5112 days || 1.3402 × 1018 picoseconds (i.e., 10-12 seconds), making a joke how π is written as "pi"
|-
| 15 || Aug 29 || one baker's fortnight (15 days) || 15 days || See day 75 (Jun 30)
|-
| 14 || Aug 30 || one baker's dozen (13) baker's days (25 hours) || 13.5416 days || 325 hours; see day 75 (Jun 30)
|-
| 13 || Aug 31 || 300 hours || 12.5 days ||
|-
| 12 || Sep 1 || one million seconds || 11.57 days ||
|-
| 11 || Sep 2 || one nonstop bike ride from NYC to LA || 10.54 days || Google maps estimates the trip at 253 hours
|-
| 10 || Sep 3 || 1/1,000th of a generation || 9.86 days || See day 79 (Jun 26)
|-
| 9 || Sep 4 || 777,777 seconds || 9.002 days ||
|-
| 8 || Sep 5 || 100 viewings of ''Groundhog Day'' || 7.014 days || Based on a running time of 101 minutes
|-
| 7 || Sep 6 || 100 games of ''Lincoln Kissing'' (Fourscore and seven minutes in Heaven) || 6.04 days || 8,700 minutes
|-
| 6 || Sep 7 || one pico-universe-lifetime || 5.04 days || See Day 51 (Jul 24)
|-
| 5 || Sep 8 || the ''Baby Shark'' chorus for a family of 50,000 sharks || ||
|-
| 4 || Sep 9 || one centiyear || 3.6525 days || 365.25 days * 1/100
|-
| 3 || Sep 10 || Cyndi Lauper's ''Time After Time'' played 1,000 times || 2.79 days || Based on a length of 4 minutes, 1 second
|-
| 2 || Sep 11 || ''Speed'' (1994) played at one frame per second || 1.933 days || {{w|Speed_(1994_film)}} has runtime of 116 minutes = 6,960 seconds = 167,040 film frames at standard frame rate of 24 frames/second
|-
| 1 || Sep 12 || F(99) where F(N) means sing all the verses of ''N Bottles of Beer On the wall'' followed by F(N-1) || 0.7639 days || Each iteration contains ''N'' verses. ''N + N-1 + N-2 ... + 1'' equals ''N * (N+1) / 2'', so 99 recursions = 4950 verses. Using the same 13-second (72 bpm) rate as Jun 29, this is close to 18 hours. Probably refers to Donald Knuth's article {{w|The Complexity of Songs}}.
|-
| 0 || Sep 13 || ''What If? 2'' release day || ||
|}

The title text refers to the recursive time period on Sep 12. If you don't stop when you reach N=0 bottles, the repetition never ends, so that time interval beecomes infinite. He likens it to {{w|The Song That Never Ends}}, another repetitive children's song, which is specifically intended to go on forever. The difference is that the Beer song has a natural stopping point at 0, while ''The Song That Never Ends'' is completely repetitive.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}

2636: What If? 2 Countdown

2022-06-23T11:31:23Z

172.70.110.121: /* Explanation */

Talk:2634: Red Line Through HTTPS

2022-06-19T00:28:46Z

172.70.110.121: c

HTTPS was standardized in 2000 or so, so 2015 is quite a stretch for a site to not use it because the site was last updated before HTTPS was widely available.
With pretty much any browser now, a red line through HTTPS means that the site _is using HTTPS_, but it is _not trusted by the browser_ (due to e.g. the certificate being self-signed or expired).
[[User:Darrylnoakes|Darrylnoakes]] ([[User talk:Darrylnoakes|talk]]) 04:28, 18 June 2022 (UTC)

:I think the intended joke is that the site's certificate expired in 2015, instead of the site is not using HTTPS. [[Special:Contributions/108.162.221.101|108.162.221.101]] 06:29, 18 June 2022 (UTC)

:2015 is when the first Let's Encrypt certs were issued, and 2016 is when LE became generally available to the public and thus when free SSL/TLS became very very easy for just about anyone setting up a web server, hence the comic citing 2015. However even with a valid cert you might have a number of issues, like [https://www.mixedcontentexamples.com/ mixed content]. At least in Firefox, an expired cert gives a big warning screen that gives you an option to add a security exception; I don't care enough to install Chrom{e,ium} to test its UI. [[Special:Contributions/172.69.69.250|172.69.69.250]] 08:30, 18 June 2022 (UTC)

::Chrome has this warning screen including an option to bypass the warning as well. I believe all browsers do. I think the only exception to this is when a site has strict transport security enabled. [[User:Jespertheend|Jespertheend]] ([[User talk:Jespertheend|talk]]) 10:49, 18 June 2022 (UTC)

Not sure it's true that if there is a problem with HTTPS like an expired cert that the connection is made with HTTP instead. [[Special:Contributions/172.69.79.201|172.69.79.201]] 10:11, 18 June 2022 (UTC)

:It's not, it still uses the https connection. It only indicates that the connection might not be secure anymore and anyone could be listening in at that point. [[User:Jespertheend|Jespertheend]] ([[User talk:Jespertheend|talk]]) 10:49, 18 June 2022 (UTC)

I actually am bemused by this. Not sure if I only visit the wrong (or right?) websites with the wrong (or right?) browsers, but I don't recall ever notably having seen struck-red links. (Perhaps I have, and assumed it was a site informing me that they were dead links, not now followable?) I ''do'' occasionally follow a normal-looking link (maybe locally CSSed in a over-riding manner of format?) and I get the browser load up a whole-screen "Problem with certificate (Are you sure? Jump through hoops for me to progress.)" which I may then take under considered advisement but mostly has me checking I'm not being spoofed as to the destination or something. Is this where the red strikethrough appears for others?
 I also have at least one site that is steadfastly still HTTP-only, and neither I nor my various browsers have any problem with it as I know what I'm doing, whilst the browsers just go there without particular complaint or anything more than usual addressbar clues... I might have "added to exception from warning" once or twice in the distant past, but not in every case. So I'm learning something here, but I don't know what. Sounds like something Edge would do, but I don't use Edge... I'm generally on Chrome, Firefox and a handful of 'lesser' flavours, all definitely updated. [[Special:Contributions/172.70.90.173|172.70.90.173]] 11:21, 18 June 2022 (UTC)

:You can find some examples of the red line on https://badssl.com/, but pretty much in all cases you get a full page warning first that something is amiss. You can also try out the http connection at http://http.badssl.com/, http connections are a bit more complicated. Some browsers don't show a warning at all, while others only show a gray 'insecure' label in front of the url. And as can be seen here [https://blog.chromium.org/2017/04/next-steps-toward-more-connection.html], the plan is to eventually show similar warnings for HTTP sites as what is currently shown for HTTPS sites with a failed certificate. [[User:Jespertheend|Jespertheend]] ([[User talk:Jespertheend|talk]]) 11:32, 18 June 2022 (UTC)

I've made a rather large change to the page to better explain the meaning of a red line through https. I removed any mentioning of using the HTTP protocol as that is incorrect. If a browser uses the HTTP protocol it is shown in the url using 'http://'. Since the comic was talking about a red line through 'https' I'm assuming the usage of the HTTP protocol is unrelated here.
Though it's possible I removed some more information from the page that might still be desired. Such as the mentioning of AI-generated spam sites and man in the middle attacks. These seemed redundant to me for explaining the joke.
I also put some more emphasis on the red line usually meaning that something bad is going on. Browser venders put a lot of effort in security, and having everyone think that a red line is not that big of a problem is the last thing they'd want. [[User:Jespertheend|Jespertheend]] ([[User talk:Jespertheend|talk]]) 11:23, 18 June 2022 (UTC)

While it's true that some browser security warnings are false alarms, I think that paragraph is missing the point of the comic. Cueball is assuming that any site that's been around for years must be operated well. But often the maintainers of the site get complacent and don't update to newer standards. And even if the real site is legit, the security warning can mean that traffic has been intercepted, so you're not actually going to the real site. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 13:40, 18 June 2022 (UTC)

I presumed this was about using outdated protocols like TLS 1.0 or weak ciphers. [[Special:Contributions/172.70.110.121|172.70.110.121]] 00:28, 19 June 2022 (UTC)

Talk:2631: Exercise Progression

2022-06-11T11:05:28Z

172.70.110.121:

The bot appeared to have not created the page, so I created it- apologies for any mishaps that I might've caused as a result. [[User:Char Latte49|Wielder of the Staple Gun]] ([[User talk:Char Latte49|talk]]) 02:42, 11 June 2022 (UTC)

I replaced the comic image, which was the 2x size image, with the correct size image from XKCD. [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 03:07, 11 June 2022 (UTC)

;"[https://www.explainxkcd.com/wiki/index.php?title=2631:_Exercise_Progression&oldid=286674 CRAPDALIZER]"?
Witw is a crapdalizer? [[Special:Contributions/172.70.126.221|172.70.126.221]] 03:42, 11 June 2022 (UTC)
:I would guess WotSG couldn't think of what to put there and made up a silly nonsense word. It's also an anagram of "lizard caper"... Anyway, I've changed it to something a bit more relevant. (Not sure if I should have deleted the "Please change this comment" part as well.)[[Special:Contributions/172.70.174.159|172.70.174.159]] 05:02, 11 June 2022 (UTC)
::Sounds like more of the crapper syndrome we have had. It is confusing with such a comment here, when the word is removed from the explanation, so I have [https://www.explainxkcd.com/wiki/index.php?title=2631:_Exercise_Progression&oldid=286674 linked to a version] of the explanation with the word in place in the incomplete reason. Also please do not add sections in the talk page... --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 08:23, 11 June 2022 (UTC)

Surprised that there was STILL no Explanation or Transcript at 2am EST, so since I fully understand this one (I feel like I wrote this comic, LOL!) I gave it a shot. '''I''' feel like they're complete and thorough, but last time my writing was completely replaced, LOL! [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 06:17, 11 June 2022 (UTC)

I was a nerd, but discovered exercise around 2012 and became very active. After the social media political stuff around 2013-2016, my curve shifted from the normal one to Randall's, incredibly hard to do things other than what's supported by the patterns. I don't think Randall's curve is natural, I think he was hit by the influence stuff too. [[Special:Contributions/172.70.110.121|172.70.110.121]] 11:05, 11 June 2022 (UTC)

Talk:2631: Exercise Progression

2022-06-11T11:05:06Z

172.70.110.121:

The bot appeared to have not created the page, so I created it- apologies for any mishaps that I might've caused as a result. [[User:Char Latte49|Wielder of the Staple Gun]] ([[User talk:Char Latte49|talk]]) 02:42, 11 June 2022 (UTC)

I replaced the comic image, which was the 2x size image, with the correct size image from XKCD. [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 03:07, 11 June 2022 (UTC)

;"[https://www.explainxkcd.com/wiki/index.php?title=2631:_Exercise_Progression&oldid=286674 CRAPDALIZER]"?
Witw is a crapdalizer? [[Special:Contributions/172.70.126.221|172.70.126.221]] 03:42, 11 June 2022 (UTC)
:I would guess WotSG couldn't think of what to put there and made up a silly nonsense word. It's also an anagram of "lizard caper"... Anyway, I've changed it to something a bit more relevant. (Not sure if I should have deleted the "Please change this comment" part as well.)[[Special:Contributions/172.70.174.159|172.70.174.159]] 05:02, 11 June 2022 (UTC)
::Sounds like more of the crapper syndrome we have had. It is confusing with such a comment here, when the word is removed from the explanation, so I have [https://www.explainxkcd.com/wiki/index.php?title=2631:_Exercise_Progression&oldid=286674 linked to a version] of the explanation with the word in place in the incomplete reason. Also please do not add sections in the talk page... --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 08:23, 11 June 2022 (UTC)

Surprised that there was STILL no Explanation or Transcript at 2am EST, so since I fully understand this one (I feel like I wrote this comic, LOL!) I gave it a shot. '''I''' feel like they're complete and thorough, but last time my writing was completely replaced, LOL! [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 06:17, 11 June 2022 (UTC)

:I was a nerd, but discovered exercise around 2012 and became very active. After the social media political stuff around 2013-2016, my curve shifted from the normal one to Randall's, incredibly hard to do things other than what's supported by the patterns. I don't think Randall's curve is natural, I think he was hit by the influence stuff too. [[Special:Contributions/172.70.110.121|172.70.110.121]] 11:05, 11 June 2022 (UTC)

2628: Motion Blur

2022-06-04T03:33:59Z

172.70.110.121: Undo revision 286160 by 172.70.210.125 (talk)

{{comic
| number = 2628
| date = June 3, 2022
| title = Motion Blur
| image = motion_blur.png
| titletext = I can't speak for your other subjects, but MY motion was as smooth and natural as the framerate allowed.
}}

==Explanation==
{{incomplete|Created by a bBboOotTt - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
[[White Hat]] is recording a video while rotating (''panning'') the camera. [[Cueball]] notices that the camera's shutter speed is too fast, which could cause the result to look unnatural or too sharp when turning the camera. Cueball decides to solve this problem by making himself blurrier than normal, counteracting the problems of the high shutter speed.

This is similar to a trick actually 'used' by {{w|Flash (DC Comics character)#Jay_Garrick|some fictional characters}} who have the power to make themselves unclear to observers or cameras alike.

When light hits a human's retina, it is perceived for a short while even after the light has ceased. This means that objects moving across a human's field of vision at a sufficient speed will naturally appear blurry – in our perception, the light arriving right now from the trailing part of the object will mix with the light that arrived a moment earlier, from the leading part of the object.

A camera's shutter speed is the amount of time that the shutter is open for each frame, allowing the image sensor to capture light. If the shutter speed is too high, this blurring will not occur, and the motion will look unnaturally crisp – if something is too small and/or too quick, the illusion of motion may disappear altogether; the object instead will appear as a brief flash of multiple objects standing still, like in the case of a fast-moving mouse cursor on a screen. In cinema, the shutter speed is generally set to double the framerate, e.g. 1/48 s for footage shot at 24 fps.

The opposing problem is that of a camera not sufficiently matching the relative motion of a moving object, with a shutter speed that is too slow (and may need to be, given the choice of aperture and lighting conditions). Sports photographers must learn how to scan-and-pan their subjects (runners, horses, vehicles, etc) with enough synchronicity to capture them sharply, and possibly seemingly hanging frozen in mid-air against an artistically-blurred background.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[A strip of three panels, featuring White Hat, Cueball and Ponytail. Cueball and Ponytail stand next to each other and White Hat stands to the left of them.]

:[White Hat is facing away from Cueball and Ponytail, and holds a camera.]
:White Hat: Okay, I'm going to pan around.
:Cueball: No, wait, your shutter speed is too fast, it will look choppy if—

:[White Hat turns towards Cueball and Ponytail, now pointing the camera away from the viewer. Cueball clenches his fists and hunches his shoulders.]

:Cueball: ''Hnnnnngh''

:[White Hat is now facing Cueball and Ponytail. Cueball now appears blurry while the others appear similar as to in previous panels.]

:[Caption below panel:]
:Expert photographers can learn to generate their own motion blur to compensate for other people's bad camera settings.
{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring White Hat]]

2627: Types of Scopes

2022-06-02T01:39:27Z

172.70.110.121:

{{comic
| number = 2627
| date = June 1, 2022
| title = Types of Scopes
| image = types_of_scopes.png
| titletext = An x-ray gyroscope is used to determine exactly which toppings they included in the pita.
}}

==Explanation==
{{incomplete|Created by a BOT WHO DIDN'T REMEMBER TO STOP TROLLS FROM SPAMMING THE WRONG IMAGE AND THIS EDITOR IS REALLY SALTY ABOUT THAT...-OSCOPE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
''{{w|Electron microscopes}}'', ''{{w|Calorimetric Electron Telescope|electron telescopes}}'' and ''{{w|radio telescopes}}'' are special forms of {{w|microscopes}} and {{w|telescopes}}, respectively. This comic explores what you could do with a hypothetical "electron ___-scope" and "radio ___-scope" for other "regular" items whose name also ends in -scope (namely: {{w|periscope}}, {{w|stethoscope}}, {{w|kaleidoscope}}, {{w|gyroscope}} and {{w|horoscope}}).

The third column with "radio" often plays on different meanings of the word ''radio:'' 1) related to radiation and 2) a device for receiving radio communication or broadcasts.

The title text makes a pun on "gyroscope" and a middle-eastern pita wrap called a "gyro".
===Table with scopes===
{| class="wikitable"
|+ What the words could mean according to the comic
|-
! Word !! Regular ___ !! Electron ___ !! Radio ___
|-
| Microscope || A laboratory instrument used for magnifying small objects. || ''Really exists:'' A microscope that uses a beam of accelerated electrons as a source of illumination, has a higher resolution than a conventional microscope. || Simply a microscope that one would use when repairing a radio.
|-
| Telescope || An optical instrument used for observing distant objects. || ''{{w|Calorimetric Electron Telescope|''Really exists''}}'': A type of telescope used to detect electrons and other high-energy particles, such as cosmic rays. || ''Really exists:'' A directional antenna used to detect radio waves from astronomical radio sources in the sky.
|-
| Periscope || Periscopes allow submarine crews to watch what happens above the water surface, without exposing the submarine to enemy observers, or enemy radars. In practice, periscope use is minimized because periscopes are still observable, but to a lesser degree. || An electron microscope seemingly mounted on a periscope. Examining enemy boats like a periscope, with the detail of an electron microsope. This would not be useful in combat. || In principle, the German navy has invented radio periscopes during World War 2. The {{w|Metox radar detector}}'s early antenna had to be built up after surfacing, and dismantled before diving. Later, the fixed ''Bali'' antenna could act like a true periscope, in order to detect aircraft and ships that were using radar to hunt submarines.

Radio signals do not propagate well in water, so raising a radio receiver above the water would be necessary for listening to {{w|NPR}} (National Public Radio, a popular public radio network in the United States) or any radio station which is not in the {{w|extremely low frequency}} band.
|-
| Stethoscope
|| A medical device for listening to sounds made by a patient's body, for example the heart. Has a disc-shaped resonator that is placed against the patient's skin.
|| If the resonator is emitting electromagnetic radiation, it could burn the skin due to its close proximity.
|| Normally, the sounds are transmitted to an earpiece that the examiner wears. There are also recording stethoscopes. A radio stethoscope would transmit the sound either directly via radio waves, or send it to a radio station such as NPR where it could then be broadcasted.
|-
| Kaleidoscope || A optical instrument which uses two or more tilted reflectors to show a regular symmetrical pattern || Seemingly a pun of electron "collide"-oscope, as electron collisions generate {{w|Bremsstrahlung}}. || The scan button on a radio scans through many frequencies, and the radio station changes a lot, depending on the frequency. The rapid change is reminiscent of a normal kaleidoscope.
|-
| Gyroscope || Gyroscopes are used for {{w|inertial navigation}}, for example. || Gyroscopes make stuff point in certain directions by spinning. An {{w|Electromagnet}} uses sometimes-spinning electric fields to induce a magnetic field, moving magnetic stuff and, in some instances, making it point in a certain direction. || A music turntable spins a vinyl record to stimulate an electromagnetic needle, which plays music. Such devices are common in radio stations.

In theory, radio waves could be sent around in a triangular pattern, thus replicating the existing {{w|ring laser gyroscope}}.
|-
| Horoscope
|| In common usage, predictions or advice given based on the position of stars and planets. Proven to be unscientific junk.
|| Predicting the position of a particle, such as an electron (possibly based on the position of stars and planets). In a funny twist, the exact location of an electron cannot be determined, due to Heisenberg's uncertainty principle.
|| Predictions or advice given based on the radiation emitted by exploding stars or galaxies.
|}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
Content is a table, with column headings "Regular ''Blank'' Scope", "Electron ''Blank'' Scope", and "Radio ''Blank'' Scope". Row headings are "Micro", "Tele", "Peri", "Stetho", "Kaleido", "Gyro", and "Horo".

;Regular Microscope
:Look at small stuff
;Electron Microscope
:Look at ''really'' small stuff
;Radio Microscope
:Figure out why your radio broke
;Regular Telescope
:Look at stuff that's far away
;Electron Telescope
:Detect cosmic rays
;Radio Telescope
:Look at distant high-energy stuff
;Regular Periscope
:Look for enemy ships
;Electron Periscope
:Examine the hull of an enemy ship for structural flaws
;Radio Periscope
:Let the crew of your submarine listen to NPR
;Regular Stethoscope
:Listen to a patient's chest
;Electron Stethoscope
:Burn a patient's skin
;Radio Stethoscope
:Play the noises from a patient's chest on NPR
;Regular Kaleidoscope
:See cool shapes and colors
;Electron Kaleidoscope
:See cool Bremsstrahlung
;Radio Kaleidoscope
:Another word for the "Scan" button
;Regular Gyroscope
:Balance by spinning
;Electron Gyroscope
:Another word for electromagnet
;Radio Gyroscope
:Another word for turntable
;Regular Horoscope
:Get random life advice
;Electron Horoscope
:Predict a particle's quantum state
;Radio Horoscope
:Get random life advice from exploding galaxies

{{comic discussion}}

[[Category:Charts]]
[[Category:Food]]
[[Category:Science]]
[[Category:Space]]

2627: Types of Scopes

2022-06-01T17:22:04Z

172.70.110.121: yknow

{{comic
| number = 2627
| date = June 1, 2022
| title = Types of Scopes
| image = types_of_scopes.png
| titletext = An x-ray gyroscope is used to determine exactly which toppings they included in the pita.
}}

==Explanation==
{{incomplete|Created by a BOTOSCOPE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

-oh my science "examine, inspect, look to or into, consider". There are many such words in the English language.

''Electron microscopes'', ''electron telescopes'' and ''radio telescopes'' are special forms of microscopes and telescopes, respectively. This comic explores what you could do with a hypothetical "electron ___-scope" and "radio ___-scope" for other words also ending in -scope (namely: periscope, stethoscope, kaleidoscope, gyroscope and horoscope). The definition of the word itself ("regular ___-scope") is also given.

The third column often plays on different meanings of the word ''radio:'' 1) related to radiation and 2) a device for receiving radio communication or broadcasts.

{| class="wikitable"
|+ What the words could mean according to the comic
|-
! Word !! Regular ___-scope!! Electron ___-scope !! Radio ___-scope
|-
| Micro- || || ''Really exists'' || Simply a microscope for looking at your radio.
|-
| Tele- || || ''Really exists'' || ''Really exists''
|-
| Peri- || Periscopes allow submarine crews to watch what happens above the water surface, without exposing the submarine to enemy observers, or enemy radars. In practice, periscope use is minimized because periscopes are still observable, but to a lesser degree. || An electron microscope seemingly mounted on a periscope. Examining enemy boats like a periscope, with the detail of an electron microsope. This would not be useful in combat. || In principle, the German navy has invented radio periscopes during World War 2. The {{w|Metox radar detector}}'s early antenna had to be built up after surfacing, and dismantled before diving. Later, the fixed ''Bali'' antenna could act like a true periscope, in order to detect aircraft and ships that were using radar to hunt submarines.
|-
| Stethoscope
|| A medical device for listening to sounds made by a patient's body, for example the heart. Has a disc-shaped resonator that is placed against the patient's skin.
|| If the resonator is emitting electromagnetic radiation, it could burn the skin due to its close proximity.
|| Normally, the sounds are transmitted to an earpiece that the examiner wears. There are also recording stethoscopes. A radio stethoscope would transmit the sound either directly via radio waves, or send it to a radio station such as NPR where it could then be broadcasted.
|-
| Kaleidoscope || || Seemingly a pun of electron "collide"-oscope, as electron collisions generate {{w|Bremsstrahlung}}. ||
|-
| Gyroscope || Gyroscopes are used for {{w|inertial navigation}}, for example. || || In theory, radio waves could be sent around in a triangular pattern, thus replicating the existing {{w|ring laser gyroscope}}.
|-
| Horoscope
|| In common usage, predictions or advice given based on the position of stars and planets. Proven to be unscientific junk.
|| Predictions based on the position of a particle, such as an electron. In a funny twist, the exact location of an electron cannot be determined, due to Heisenberg's uncertainty principle.
|| Predictions or advice given based on the radiation emitted by exploding stars or galaxies.
|}

The title text makes a pun on "gyroscope" and the Greek foods {{w|Gyros}} and {{w|Pita}}.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}

Talk:2626: d65536

2022-05-31T09:41:24Z

172.70.110.121:

I wonder: can we even make a fair polyhedron with 65536 faces? In Randal's illustration, the faces seem to be irregular hexagons. [[Special:Contributions/172.70.130.105|172.70.130.105]] 21:37, 30 May 2022 (UTC)
: This is better than my question, which was simply if you could tile a sphere with these. [[Special:Contributions/172.70.211.36|172.70.211.36]] 23:01, 30 May 2022 (UTC)
:Definitely possible, just create two identical right pyramids with a 32768-gon base and glue the bases together. [[User:Clam|Clam]] ([[User talk:Clam|talk]]) 23:53, 30 May 2022 (UTC)
: Would this design be fair? Consider a set of 256 lines of latitude overlapping another set, with the second set's polar axis at the equator of the first. Cut flat quadrangles between the intersection points of the lines of latitude. Anyway, it looks like Randall's design uses hexagonal faces. [[Special:Contributions/172.70.110.121|172.70.110.121]] 09:41, 31 May 2022 (UTC)

I don't know why it's so big? Seems like it should have a diameter of approx. 1 meter. [[Special:Contributions/172.70.130.105|172.70.130.105]] 21:37, 30 May 2022 (UTC)
: Cueball is 50 pixels high. The ball is 340 px high. Assuming Cueball is an average-height male (1.7m), and is standing the same distance from the viewer as the center of the ball, roughly how large is each face of the polygon? Area of a sphere is 4.pi.r.r, r=0.85, so 9.08 m^2 or 9080000 mm^2, divide by number of faces, get 277 mm^2, so we get 1.6cm to a side. If I did that right, then you're right: those are fairly large faces. --[[Special:Contributions/172.69.70.39|172.69.70.39]] 05:58, 31 May 2022 (UTC)
:I ran the calculations for the Trivia section. I used 12pt font which gave each number an area of 1/6 square inch (about 1 square cm) [[Special:Contributions/162.158.106.237|162.158.106.237]] 06:57, 31 May 2022 (UTC)

Should the title and picture file use "d" or the comic's difficult to type "ᴅ"?
[[User:While False|While False]] ([[User talk:While False|talk]]) 21:55, 30 May 2022 (UTC)
:Since xkcd uses small caps as lowercase letters, the "ᴅ" should just be considered xkcd-font for "d", and as such need not be used on the title, which is not using the xkcd font.
:: Ah! [[User:While False|While False]] ([[User talk:While False|talk]]) 06:15, 31 May 2022 (UTC)

If you really did want to generate a 16 bit integer with physical dice, it would be much simpler to roll a [https://www.thediceshoponline.com/impact-opaque-hexidice-d16-hexadecimal-dice hex die] four times. [[User:Clayot|Clayot]] ([[User talk:Clayot|talk]]) 23:30, 30 May 2022 (UTC)
:Rolling a binary die 16 times would also work. You can get binary dice for 1¢ each. [[Special:Contributions/108.162.245.69|108.162.245.69]] 01:31, 31 May 2022 (UTC)
::Those 1¢ "dices" are not exactly guaranteed to be random. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 06:12, 31 May 2022 (UTC)
:::They seem as random as other dice? Am I wrong? [[Special:Contributions/172.70.230.63|172.70.230.63]] 09:33, 31 May 2022 (UTC)

I think the hardest part (or maybe second-hardest part) is figuring out which facet is the one on top. [[Special:Contributions/162.158.78.109|162.158.78.109]] 00:46, 31 May 2022 (UTC)
:Roll it on a glass table, check from below which face it's landed on instead. Wait until it has settled safely, though, or it might land on ''your'' face! [[Special:Contributions/172.70.90.227|172.70.90.227]] 04:58, 31 May 2022 (UTC)
:: Good plan. Assuming standard dice design, subtract the value from 65537 to get the value of the uppermost face. --[[Special:Contributions/172.69.70.39|172.69.70.39]] 05:58, 31 May 2022 (UTC)

What material should it be to be light enough to easily roll it but cheap enough that doing the 1,5 meters doest cost a fortune ? Sorry if the question is not clear. [[Special:Contributions/141.101.69.30|141.101.69.30]] 05:50, 31 May 2022 (UTC)
:I recommend making it hollow. You could probably do something like this for $3000 if you made it out of 1/8th inch acrylic plate. [[Special:Contributions/162.158.106.237|162.158.106.237]] 07:02, 31 May 2022 (UTC)
:At first I thought aluminum for sturdiness, but really you could make this out of cardboard for dirt cheap, lasercutting precise shapes, but you'd have to design its structural frame to keep it intact, exchanges design effort for price. [[Special:Contributions/172.70.230.63|172.70.230.63]] 09:32, 31 May 2022 (UTC)

I disagree with this dice being really random. Like, sure, if thrown correctly, but that's going to be quite hard. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 06:12, 31 May 2022 (UTC)

Should it be related to https://xkcd.com/221/ ? [[Special:Contributions/162.158.183.246|162.158.183.246]] 08:07, 31 May 2022 (UTC)

2625: Field Topology

2022-05-29T03:01:32Z

172.70.110.121:

{{comic
| number = 2625
| date = May 27, 2022
| title = Field Topology
| image = field_topology.png
| titletext = The combination croquet set/10-lane pool can also be used for some varieties of foosball and Skee-Ball.
}}

==Explanation==
{{incomplete|Created by SOMEBODY HOMEOMORPHIC TO YOUR DOG - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic strip depicts a situation where the common practice of multi-use athletic facilities has been organised and constructed based soley on criteria in which sports are grouped by the {{w|topology|topological equivalence}} of their fields. (not to be confused with {{w|Field (mathematics)|mathematical fields}}, or the {{w|Fields Medal}} prize -- although successfully {{w|Straightedge and compass construction|constructing}} these fields might lead to medals of one kind or another being granted).

In topology, shapes which can be smoothly deformed into one another without adding or removing holes are considered to be "equivalent".

{{w|Baseball}}, and {{w|tetherball}} are played on fields without any holes that the ball or players can completely pass through, so they are ({{w|Group (mathematics)|grouped}}) (physically and mathmatically) into one continuous field without holes. The goals on a {{w|soccer}} field presumably do not create holes because the goalposts and crossbar are connected to the field by the net, so the goals and field are topologically equivalent to a smooth disc.

{{w|Volleyball}} and {{w|badminton}} are played on a court through the center of which passes a net suspended from poles, and the {{w|high jump}} has a bar that contestants jump over. The space bounded by the bottom of the net (or bar), the supporting poles, and the ground can be considered to be a hole, so their fields all have one "hole".

A basketball court has two holes, the nets. Parallel bars can be thought of as two rectangles and thus as two topographical "holes". The inclusion of an American football field is perplexing. Commonly, an American football field uses a "Y" shaped upright, making the field topologically equivalent to a plane. However, at lower levels of play (primary and secondary schools), sometimes an "H" shaped upright is used, which creates a topological hole under the crossbar at both ends of the field. The comic might instead refer to Gaelic football or Rugby, both of which use "H" shaped goals and are called "football" in certain contexts.

The lane dividers in a swimming pool create bounded holes on the 'playing surface' equivalent to the number of lanes. And each hoop in croquet is a hole with one edge bounded by the playing surface. Similarly, as mentioned in the title text, this configuration is also {{w|homeomorphism|homeomorphic}} to a {{w|foosball}} table (with each rod sustaining the player figures above the table defining a hole) or a {{w|Skee-Ball}} lane (which is even more straightforward, as it is just a plane with several holes in which to throw balls).

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

A row of four signs, each held up by two posts, followed by a row of four roughly oblong shapes, one for each sign. The signs and oblong shapes are shaded as if three-dimensional objects, all being flattish with a small third dimension. The four oblongs are presented at an oblique angle, as if they are in "front" of the signs extending towards the viewer. All but the first oblong have various numbers of holes "through" them.

zero holes: "Baseball. Soccer. Tetherball."

one hole: "Volleyball. Badminton. High jump."

two holes: Basketball. Football. Parallel bars."

nine holes: "Olympic swimming. Croquet."

Image caption: "No one ever wants to use the topology department's athletic fields."

{{comic discussion}}
[[Category:Math]]
[[Category:Sport]]

2625: Field Topology

2022-05-27T14:21:50Z

172.70.110.121: /* Explanation */

2619: Crêpe

2022-05-13T14:08:08Z

172.70.110.121: /* Transcript */

{{comic
| number = 2619
| date = May 13, 2022
| title = Crêpe
| image = crepe.png
| titletext = A medicine that makes you put two dots over your letters more often is a diäretic.
}}

==Explanation==
{{incomplete|Created by a CRÊPË - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

Cueball: Check out this crêpe I made! 
Megan: Weird circumflex, but okay.

{{comic discussion}}

2619: Crêpe

2022-05-13T14:07:51Z

172.70.110.121:

{{comic
| number = 2619
| date = May 13, 2022
| title = Crêpe
| image = crepe.png
| titletext = A medicine that makes you put two dots over your letters more often is a diäretic.
}}

==Explanation==
{{incomplete|Created by a CRÊPË - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

Cueball: Check out this crêpe I made!
Megan: Weird circumflex, but okay.

{{comic discussion}}

Talk:791: Leaving

2022-05-07T15:36:18Z

172.70.110.121:

RIP, dearly beloved wife who died in a freak accident with a supermarket shelf while trying to buy spray cleaner. '''[[User:Davidy22|{{Color|#707|David}}y²²]]'''[[User talk:Davidy22|<tt>[talk]</tt>]] 02:18, 24 April 2013 (UTC)
:She is survived by lonely dude staring at cat vomit. [[User:Cflare|Cflare]] ([[User talk:Cflare|talk]]) 20:58, 7 August 2014 (UTC)
::While - after getting the bad news - he raced down the flight of stairs, tripping, falling, rolling, and breaking his neck against the wall at the end of the stairs, the cat was cleaning itself. When it heard the impact downstairs it jumped startled, went over into the patch of sun, laid down, and said, "Meow!" It survived them both... {{unsigned ip|162.158.90.192}}
:Just added a description of the title text, but wanteed to make sure that it was satisfactory before removing the incomplete tag. [[Special:Contributions/108.162.216.232|108.162.216.232]] 21:47, 16 March 2018 (UTC)
... Does the blob of vomit have a catface? {{unsigned ip|162.158.111.235}}

Conversely, this makes me want to start saying really weird things to people before they leave. —[[User:Kazvorpal|Kazvorpal]] ([[User talk:Kazvorpal|talk]]) 21:38, 28 October 2019 (UTC)

"I will never forget the last thing I said to her. Maybe if I hadn't asked for that, she wouldn't have gotten into a fight with a murderer over the last bottle of spray cleaner."

1889: xkcd Phone 6

2022-05-04T19:55:39Z

172.70.110.121: Undo revision 241949 by Ex Kay Cee Dee (talk)

{{comic
| number = 1889
| date = September 13, 2017
| title = xkcd Phone 6
| image = xkcd_phone_6.png
| titletext = We understand your privacy concerns; be assured that our phones will never store or transmit images of your face.
}}

==Explanation==
This is the sixth entry in the ongoing [[:Category:xkcd Phones|xkcd Phone series]], and once again, the comic plays with many standard tech buzzwords, and horribly misuses all of them, to create a phone that sounds impressive but self-evidently isn't to even the most ignorant customer. The previous comic in the series [[1809: xkcd Phone 5 ]] was released 7 months before this one and the next [[2000: xkcd Phone 2000]] was released 8 and a half months later.

This comic was released the day after Apple announced their new {{w|iPhone 8}} and the higher-end {{w|iPhone X}} (pronounced iPhone 10) with facial recognition features.

===List of features (clockwise from center/top)===

; Front camera (centered for eye contact during video chat)
: A front camera has become a common feature of smartphones. The camera lens is located on the same side of the phone's case as the main screen, making it possible to capture the image of the user's face looking at the screen and display the interlocutor's face on the screen simultaneously, enabling video chat. However, as the camera is usually located above the screen, when the user looks at the displayed image of the other person they direct their eyes at the center of the screen and not at the camera's lens. This makes it appear on the other end of the chat as if the person talking was looking down and not making eye-contact, which can be an uncomfortable situation for many people. For this reason, professionals involved in movie or TV-making, like actors or reporters, are trained to look straight into the camera's lens while talking, which creates impression of looking straight at the viewer's face. During a video chat, however, looking into the lens of an above-screen camera does not allow one to see the interlocutor's face clearly because it is then in the peripheral field of vision.

: To solve this conundrum, Randall proposes locating the camera lens right in the middle of the screen. The user looking at the the other person's face on the screen would then also be looking at the lens, creating an impression on the other end of the chat that they are looking straight at the other person. This is absurd, since the lens would then take place of some of the center pixels of the screen, which would probably mean that it could not display the center part of the captured image of the other person's face. This could include features such as eyes and/or lips, which play an important part in non-verbal communication. Locating the camera lens in this way would probably also interfere with the touch-screen function. It would probably make other applications on the phone difficult to use, since virtually no user interface is designed to accommodate a blind spot in the center.

: The idea of having the camera in the middle of the screen is only currently absurd, however, as advances in technology may eventually enable such a feature to work without disturbing the appearance or function of the phone's display, unlike the visual disturbance clearly indicated in the comic. For instance, previous technological advancements have improved the functionality of the display, starting with adding touch sensing. The touch sensitive hardware of the phone is located in a thin layer above the hardware, that generates the image for the display, and capacitive touch sensing technology is less obtrusive than previous resistive sensing. While it has yet to be released to market, certain manufacturers are aiming to place a phone's fingerprint reader underneath the screen, for seamless functionality. Although it may be difficult at this point, figuring out a way to have a camera capture images through the array of pixels on the screen is not completely beyond imagination.

; Full-width rear camera
: Historically, there has been an 'arms race' among phone manufacturers to increase the 'size' of the rear camera, in terms of the number of pixels they can capture. This is not typically accompanied by equivalent increases in physical size, though. Phone cameras tend to have lenses which are quite small, and round or square -- measuring the same in width as in height. On this phone, the 'full-width' lens appears to be a long, thin strip, like an oval or rectangle shape. This could allow the camera to gather a lot more light, potentially working in low light situations. However the lens would be more vulnerable to damage and dirt. Unless a very large sensor was used, focusing the image could be a problem, since cell phones are typically not very deep.

; CDC partnership - phone automatically administers seasonal flu vaccine to cheek every year
: U.S. {{w|Centers for Disease Control and Prevention}} is a government agency tasked with addressing public health concerns, such as infectious diseases, including seasonal flu. A common way of limiting the spread of an infectious disease is {{w|Vaccine|vaccination}}, which most often involves administering a specially prepared vaccine via an {{w|intramuscular injection}}, though researchers have investigated other delivery systems, including aerosol, or microneedle injection. Uptake of vaccination is often poor, and many governments routinely use various different campaigns and techniques to try to encourage more people to get themselves vaccinated.

: This feature implies that the phone would automatically perform some form of injection once a year, administering a vaccine via a small aperture while the user is holding the phone to their cheek during a call. However, the placement of this component is dubious, as it would line up with the user's ear, rather than their cheek, during a phone call. It may be designed to detect the fraction of a second during which your cheek would be in the appropriate position (perhaps after a phone call, as you may be dropping the phone from your ear), and administer it at that moment; this would conveniently prevent disturbances to a majority of conversations.

: A further absurdity to this feature is that the vaccine is different every year, in order to account for various mutations causing different, and typically new, strains of the virus, which is the reason it has to be administered yearly. The CDC bases the combination of strains on a best-guess of what will be the most significant strains in circulation over the upcoming year, so in order to have the current year's vaccine, the user would have to physically load the new version into the phone for later administration, or there would have to be a mechanism to synthesize the concoction on-board the phone, and an associated logistics framework and digital standards for OTA delivery of specifications for the year's vaccine.

; 12-function
: Most smartphones can be used for more than twelve different things{{Citation needed}}. However, this may refer to the twelve basic functions of algebra (identity, squaring, cubing, square root, logarithm, exponential, reciprocal, sine, cosine, greatest integer, absolute value, and logistic), or the twelve function keys on a modern keyboard (more than the ten on the original IBM PC keyboard). Alternatively, it may be a reference to calculators: basic models are sometimes referred to as four function calculators (addition, subtraction, multiplication and division), and complex scientific calculators may advertise 250 or more functions.

; Dishwasher safe
: Waterproofing has become a much-pushed feature of many recent smartphones, with manufacturers competing on the claimed resilience of their models. A phone that was truly dishwasher safe would be ahead in this race, as it would have to be able to withstand high-pressure jets of water, high temperatures, and caustic effects of detergent over significant periods. This is often listed as a selling point of items used for preparing, serving, or storing food, such as plastic containers or crockery, which a normal person might want to clean using a dishwasher, but it seems excessive for phones, which are rarely cleaned with anything more than a quick wipe, and most people would not intentionally attempt to clean in a dishwasher.

; GPS transmitter
: Many smartphones have a receiver for the {{w|Global Positioning System}}, which allows a phone to compute its position based on signals from the constellation(s) of GPS satellites. However, a device with a "GPS transmitter" would broadcast signals that would interfere with the GPS receivers of all devices nearby. This might be used in some form of differential GPS, broadcasting signals from a known location to allow more precise determination of other locations, or such a system might be used to confuse or control devices, such as drones, which navigate using GPS.

; 3-G acceleration
: This is a mixture of three unrelated concepts with similar names. In computer graphics, "{{w|Graphics processing unit|3-D acceleration}}" refers to GPU hardware that speeds up handling of three-dimensional data, such as shapes rotating in space. In physics, "3 Gs of acceleration" refers to speed increasing at a rate of 3 times the acceleration of Earth's gravity, or approximately 30 m/s². In cellular networks, {{w|3G}} refers to a standard for data communication. GPUs, accelerometers, and compatibility with 3G networks are all normal features of modern smartphones. "3-G acceleration", however, is not a real term, and doesn't describe any meaningful feature of a phone. It appears to suggest that either the phone is capable of self-propelling with 3 Gs of acceleration, which doesn't seem particularly useful, or, perhaps more feasibly, that it has some way of increasing the data transfer rate over a 3G connection.

; Portable, solar-heated
: Portability is pretty much the entire point of using a ''mobile'' phone, so advertising portability is rather redundant. Solar ''power'' charging could be a very useful feature on a phone, but solar ''heating'' usually applies to plumbing, where a water tank is heated by the sun and used to supply hot water to taps. Technically, as the sun heats up everything it shines on, the phone is in fact solar heated. However, since avoiding overheating is a particular challenge in smartphone design, deliberately capturing solar energy simply in order to heat the device would seem rather counter-productive.

; Pore-cleaning strip
: Pore-cleaning strips are sticky strips designed to be applied to the skin and then pulled away to remove dirt and oils from the pores, with the intention of reducing spots and improving the complexion. The location shown for this feature would be inconvenient and irritating, as it would come into contact with the face every time the phone was held to the ear to make a call; something sticky on that location would be very annoying for clean-shaven people and extremely painful for anyone with facial hair. It would probably also result in that strip of the screen becoming obscured by an accumulation of facial gunk. Pore strips have been mentioned before in [[777: Pore Strips]].

: This may act as a sensor for the ''Shroud of Turin-style facial transfer unlock'', whereby the phone would collect the dirt, oils, and microflora from the user's face when it is pressed against the phone, and use it to verify their identity.

; Maximum strength
: Medicines are often sold as "Maximum strength", usually indicating that they contain the highest dose of active ingredients allowed by law, or allowed without a prescription. For phones, there are sometimes "hardened" or "ruggedized" versions, which are designed to survive harsher environmental conditions, such as surviving drops and collisions, excessive water, dust, etc. ''Maximum strength'' here could indicate such a "ruggedized" phone, though this would be hard to achieve with a screen that extended past the edges.

; Never needs sharpening
: Phones do not need to be sharpened in the first place{{Citation needed}}. This is a feature more likely to be found in a knife advertisement -- the slogan is infamous for hawking knives that ''cannot'' easily be sharpened, like a serrated blade -- or a mechanical pencil. Since the screen goes past the edge, it might be sharp enough to cut through things, much like a knife, though the phone would be unsafe to carry and handle if that were the case{{Citation needed}}.

Might also refer to sharpening the camera, which usually means adjusting the lens till an object is in focus. Most phones have autofocus and rarely need to be manually sharpened.

; Can survive up to 30 minutes out of water
: This is a play on the common IP-rating of water resistance, which is typically rated for submersion to a rated depth for 30 minutes. A phone which could only be used or carried for 30 minutes before it needed to be immersed in water would be rather inconvenient, although the phone short circuiting would likely not be an issue, as the phone is "dishwasher safe."

: Alternatively, either this phone's target market could be whales, dolphins, or other marine life, such as octopodes, or the feature could be optional. While such a feature would prove to be extremely useful for aquatic customers, the "solar-heated" feature would undoubtedly be inhibited significantly as water depths increased.

; Exclusive Audubon Society app identifies birds and lets you control their flight
: The {{w|National Audubon Society}} is a non-profit organization dedicated to the conservation of nature, and mainly of birds, which also organizes open {{w|birdwatching}} events. There are apps that attempt to identify bird species, for example, from a [https://play.google.com/store/apps/details?id=com.labs.merlinbirdid.app&hl=en_GB photo] or [https://play.google.com/store/apps/details?id=com.isoperla.birdsongid&hl=en_GB audio recording] of a bird made by the smartphone itself, though the Audubon Society's [https://play.google.com/store/apps/details?id=com.audubon.mobile.android&hl=en_GB own app] does not offer anything this interactive. An app allowing you to control the bird's flight would be way cooler and might work using the built-in GPS transmitter, confusing their navigation systems. However birds do not use GPS to navigate{{Citation needed}}, and it would fly in the face of the Audubon Society's core activity. This is a reference to {{w|Unmanned_aerial_vehicle|drones}} (which could be thought of as artificial "birds") which are often controlled by a smartphone app. This may also be a reference to [[1425: Tasks]], in which an app that can recognize if a bird is on camera is proposed.

; Extra screen
:Some phones advertise an additional display or display mode, often giving access to basic information, such as battery level and notifications without needing to activate the main screen function. Typically, this would be a low-power mode of operation of the normal screen, or else a form of display on another surface of the phone, such as the side or rear. Here, it seems to be an oddly shaped rectangular extension on the bottom of the main screen. This may have been added to make up for the loss of screen estate due to the center camera.

; Wireless charging port
:A port for {{w|Inductive_charging|wireless charging}} is an oxymoron, since wireless charging has no wires and thus has no need for a port, unless it is required for fuel for a fuel cell (see clean coal, below). This may be a jab at Apple's removal of the headphone port from their previous phones.

; Safe for ages 6-8 months, 10 months, 18 months-3 years, and 12 years and older
:Usually an item is deemed safe for a particular age or older, or (in the case of toys) is recommended for a particular age range. This is unusual in that it's a hodge-podge of age ranges with no apparent reason why some ages are safe and others are not. It may be a parody of drug commercials that list several age ranges for which the drug had to be separately approved.

; Screen goes past the edge
:A parody of the trend of "edge to edge" displays in recent generations of smartphones, or phones whose screens curve partway around the edge of the phone. In this case the screen is wide enough that it ''could'' curve partway around the edge, except the spillover does not actually form to the curves, resulting in a screen that is wider than the body of the phone. If the spillover is rigid, this would make the phone rather uncomfortable to hold, and the spillover is at risk of chipping off.

; High thread count CPU
:A {{w|Thread_(computing)|CPU thread}} is a task the CPU performs. Several threads may share memory, making them a process. Threads are meant to run in parallel and the operating system distributes the workload on the available hardware execution units. These execution units are sometimes called hardware threads, especially when there is more than one per processing unit (or core). For example, the Intel Core i7 7700 is considered a 4-core, 8-thread CPU. The vague "high thread count" statement could make sense in this context, however, it is most likely a joke about bedding, where it is an actual selling point; the thread count of a textile signifies the density of fibres in the material, and a high thread count is an indicator of a high quality fabric.

; Shroud of Turin-style facial transfer unlock
:The {{w|Shroud of Turin}} contains an image of the body and face of a man, originally believed to be {{w|Jesus Christ}}, before the Shroud was found to be 1200 years too young. Some theories suggest the image was created by interaction with or transfer from the body that was wrapped in the shroud. Presumably, to unlock this phone, the user would have to physically {{w|facepalm|press their face}} against the phone, the way the Shroud-Man's image was allegedly transferred to the shroud. This is probably a reference to the iPhone X's FaceID unlock, which uses a ''photograph'' of your face, augmented with spatial information, to unlock itself, and which had attracted [https://www.wired.com/story/iphone-x-faceid-security/ significant criticism] immediately before this comic came out.

; Fonts developed by NASA
: This may be a reference to many advertisements that claim that their product uses technology developed by NASA in an attempt to make it seem more impressive. NASA technology does often tend to be quite strong and advanced, as they claim at their [https://spinoff.nasa.gov/ spin off] website. Between 1975 and 1992 NASA used the {{w|NASA insignia|"worm" logotype}} in its insignia; it was a special font that omitted the horizontal bar in the capitalized letter A. However, it would not be particularly impressive to use this, since fonts have very little to do with NASA's core operations{{Citation needed}}, and it potentially implies that it would not support many other common, and perhaps more readable, fonts.

: This may also be riffing on the {{w|Writing_in_space|urban legend}} that NASA invested vast amounts of research in developing a pen that could write in space, rather than just using a pencil.

; Includes applicator
: This is found on the packaging for many products, such as tampons, cosmetics, and paints. An applicator for a phone would be absurd, since the phone cannot be applied, spread, inserted, or attached to something else. However, this may be referring back to the aforementioned yearly vaccine.

; Burns clean coal
: Clean coal is coal that is burned so that it does not give off as much soot, sulphur dioxide, nitrogen oxides, mercury, or other pollutants as "normal" coal, or methods of burning coal that give off relatively less pollutants. This may be advertised by energy companies trying to appear to be using clean energy, due to pollution concerns. Coal burning power plants are usually quite large, so a traditional coal fired thermal-electric plant in a cell phone would be absurd. {{w|Fuel cell|fuel cells}}, which produce electricity by oxidizing some fuel, can be small enough to fit in a cell phone, but they do not typically burn coal. The cordless charging port might be a receptacle for refueling the phone, using liquid or a fuel cartridge.

; Pre-seasoned
:Pre-seasoned typically refers to cast iron cookware which is ready to use out of the box, as opposed to needing to season it with oil and heat. It can also refer to packaged meats which are ready to cook without needing to be seasoned with herbs and spices, or timber that has been dried and is ready for use. A more technical definition of 'seasoning' means operating devices, usually calibrated standards or battery cells, for a while in the factory, to make sure the device meets constant performance requirements without deviating or diminshing too much. In this sense it could apply to the battery of the phone.

; Broad-spectrum SPF 30
:The xkcd phone somehow gives a {{w|sunscreen|sun protection factor}} (SPF) 30 level of protection from sunlight, meaning that it blocks all but 1/30 of skin-burning UVB radiation from sunlight, though it is not clear whether it is the user or the phone itself which is protected. Phones do not typically require protection from sunlight{{Citation needed}}. On the other hand, if, when placed between the user and the sun, the phone allows >3% of the radiation through, this would be remarkably more translucent, and therefore less effective, than most phones (which allow much less than 1% of UVB, or any other visible or near-visible wavelength, through). It would also be an inefficient method of protection, since it would only be able to protect a relatively small patch of skin.

; College-ruled
:College-ruled is a style of notebook paper having narrower than normal lines, in order to fit more text per page. That the phone is college-ruled suggests that there are lines permanently displayed on the screen, which could obscure any images on the screen, and make any text that doesn't line up with the lines hard to read. Defective screens can show similar patterns; for example, the iPhone 6 "touch disease" causes regularly spaced vertical lines to appear on top of the screen. Here, it is possible that the manufacturer is trying to pass off screen defects as features.

; Sterile packaging
:Useful for medical supplies, less so in a phone. There are numerous studies and resulting 'news' articles looking at the number of bacteria, fecal samples, and so forth, that can be found on the typical phone, typically with a sensationalist take on how you will be 'shocked' to discover this. However, sterile packaging would do little to counter this, since most of this contamination is accumulated after the user removes the phone from the packaging and begins using it.

; Radium backlight
:The discovery of the radioactive element radium sparked a brief fad in which manufacturers of consumer products began coating them with a paint containing radium and a radioluminescent substance, such as zinc sulfide, which converted the radiation from the radium into visible light. In particular, some clock and watch makers painted the faces or hands of their timepieces, allowing the time to be read at night without an external power source for the light. However, it was eventually realized that regular exposure to radium could result in radiation poisoning, particularly for the workers assembling and painting the products. A radium-based backlight would therefore be both potentially dangerous (especially for an object carried on one's person much of the time) but also largely useless, as the radioluminescent light is rather dim compared to conventional phone back lights.

; 4K pixels (50×80)
:"4K" typically denotes a screen with a width of ~4000 pixels, such as 4K TVs, which have 3840×2160 pixels, or about 8.3 million pixels total. That would be an outstanding resolution for a cell phone. Here, however, the "fine print" in parentheses clarifies that 4000 is actually the total number of pixels, not the width, which would be remarkably low resolution for a smart phone. As a comparison, the old Commodore VIC-20, with a resolution of 176 × 184, would have over 8 times the pixels of this phone. It is more comparable to the screen resolution of the sturdy Nokia 3310, which boasted a total of 4032 pixels, positioned 84 × 48.

===Version===
In the caption below the phone [[Randall]] presents many different version numbers:
*The number 6 is in correct order of all the xkcd phones
*The {{w|Roman numerals|Roman numeral}} VIII refers to the newly announced {{w|iPhone 8}} and jokes about the Roman numeral X below
*Version number 10 is the current version of Microsoft Windows
*The {{w|iPhone X}} was announced together with the iPhone 8 by Apple on September 12, 2017, a day before this comic was released. Apple clarified that X is meant to be read as the Roman numeral for 10, so for additional absurdity two xkcd phones share the same number, using different numerals
*The number 26 refers to the number of letters in the English alphabet
*In the year 1876 {{w|Alexander Graham Bell}} received the U.S. Patent No. 174465 for the {{w|invention of the telephone}}, but there is still a {{w|Elisha Gray and Alexander Bell telephone controversy|controversy}} whether {{w|Elisha Gray}} was the first to present a working telephone.

The "nonconsecutive version number war" referenced below the version names refers to several recent phones, and possibly operating systems, released consecutively with nonconsecutive version numbers, including:
*The iPhone X (or Ten) which will be released shortly after the iPhone 8
*The Samsung Galaxy Note 7 was released after the Note 5
*The Oneplus 5 was released after the OnePlus 3T
*The ZTE Axon 7 was released after the original Axon, skipping numbers 2-6.
*Microsoft Windows has a long history of non-consecutive version numbers/names, with the most well-known releases being (in order) {{w|Windows 3.1|3.1}}, {{w|Windows NT|NT}}, {{w|Windows 95|95}}, {{w|Windows 98|98}}, {{w|Windows 2000|2000}}, {{w|Windows Me|Me}}, {{w|Windows XP|XP}}, {{w|Windows Vista|Vista}}, {{w|Windows 7|7}}, {{w|Windows 8|8}}, and {{w|Windows 10|10}}.

Randall's ludicrous naming scheme aims to 'defeat' all of these by eclipsing them. By counting parallel version numbers xkcd defeated Apple 6:2.

The symbols at the end are ™ for trademark, ® for registered trademark, and © for copyright. The degree symbol ° after the letter C could be a play with degree Celsius. The use of all four symbols after the phrase is ridiculous, as ™ and ® indicate trademarks with opposite registration statuses, slogans can't be copyrighted, and the degree symbol usually has no meaning when applied to text.

In the title text Randall recognises privacy concerns about the facial recognition feature. A picture of a face will only be used for facial recognition, but never stored on the device nor transmitted to the internet. A ''small'' side effect may be that the famous selfie pictures aren't possible anymore, as well as video calls. Ironic, considering that the reason the camera is in the middle is to allow easier video calls.

==Transcript==
:[A smartphone is shown, the screen is slightly wider than the case, in the middle is a photo lens, and at the right bottom a small extra part is added to the screen.]
:[On top a bracket ranges nearly over the entire width of the case. The text reads:]
:Full-width rear camera
:[The label at the photo lens is:]
:Front camera (centered for eye contact during video chat)
:[The label on the extra part says:]
:Extra screen
:[At the bottom below the case a label reads:]
:Wireless charging port

:[The labels left to the phone are:]
:4k pixels (50x80)
:Radium backlight
:Sterile packaging
:College-ruled
:Broad spectrum SPF 30
:Pre-seasoned
:Burns clean coal
:Includes applicator
:Fonts developed by NASA
:Shroud of turn-style facial transfer unlock
:High thread count CPU
:Screen goes past the edge
:Safe for ages 6-8 months, 10 months, 18 months-3 years, and 12 years and older

:[The labels right to the phone are:]
:CDC partnership: Phone automatically administers seasonal flu vaccine to cheek every year
:12-function
:Dishwasher safe
:GPS transmitter
:3-G acceleration
:Portable, solar-heated
:Pore-cleaning strip
:Maximum strength
:Never needs sharpening
:Can survive up to 30 minutes out of water
:Exclusive Audubon Society app identifies birds and lets you control their flight

:[Text below the phone:]
:Introducing
:'''The xkcd Phone 6, VIII, 10, X, 26, and 1876'''
:''We didn't start this nonconsecutive version number war, but we will not lose it.''™®©°

{{comic discussion}}

[[Category:xkcd Phones]]
[[Category:Comics sharing name|xkcd Phones]]

1922: Interferometry

2022-05-04T19:55:21Z

172.70.110.121: Undo revision 241951 by Ex Kay Cee Dee (talk)

{{comic
| number = 1922
| date = November 29, 2017
| title = Interferometry
| image = interferometry.png
| titletext = It's important to note that while the effective size of the dog can be arbitrarily large, it's not any more of a good dog than the two original dogs.
}}

==Explanation==

Interferometry is the practice of overlapping two different waves to get a different signal, which can be used to determine the distance between two reflecting surfaces. An {{w|astronomical interferometer}} uses this principle to build an array of separate telescopes that are able to work together as a single telescope, effectively providing higher resolution using a process known as {{w|Aperture Synthesis|aperture synthesis}}.

In the comic, [[Beret Guy]] and [[Cueball]] are walking Beret Guy's dogs when Beret Guy makes a comment on how interferometry is really cool. Beret Guy states that two dogs placed at a consistent interval will function as a larger dog — a play on the astronomical interferometer. While this idea works on waves, it probably won't work on dogs{{Citation needed}} (though since h/p=λ it might), which is why Cueball is confused and starts to correct him. Before he can respond, however, Beret Guy jumps on his "large" dog and appears to be floating in midair. The existence of large dog is further proven when it gives out a large bark. Cueball looks on speechless while Beret Guy appears to exhibit another of his [[:Category:Strange powers of Beret Guy|strange powers]].

In [[1614: Kites]], Beret Guy is "walking" a dog. It is possible that one of the dogs in this comic is the dog from Kites.

The title text states that the effective giant dog is not any more 'good' than the two original dogs. This is analogous to sensitivity for astronomical interferometers. Interferometry does not increase the light-gathering area, so it cannot view dim objects as well as a single large telescope could. This is also a reference generally to dog-owners calling their dogs "good dog" or "good boy/girl" when they behave well; presumably, Beret Guy's giant interferometry dog is only as well-behaved as the dogs they are derived from. (However, as interferometry does collect more light than any individual telescope used, the interferometry dog is presumably more good than either individual dog. Considering the destructive potential of a giant bad dog, this is a good thing.) It may also be a reference to the [http://knowyourmeme.com/memes/theyre-good-dogs-brent They're Good Dogs, Brent] meme.

==Transcript==
:[Cueball is walking behind Beret Guy, who is walking two small dogs on two leashes.]
:Beret Guy: Interferometry. Is so cool!

:[They stop and Beret Guy is holding the leashes in his hand. He has taken them off the dogs and points at the dogs, which he has placed facing outward so they are standing a couple of paces apart. The distance between them is indicated by a labeled line.]
:Beret Guy: If you put two small dogs a large distance apart, they can function as a single giant dog.
:Line: d

:[Cueball begins to speak but is cut off by Beret Guy yelling as he jumps into the space above the two dogs, with each leg a good distance above one of the dogs. (The leashes have disappeared, as well as the distance line).]
:Cueball: I'm not sure that's-
:Beret Guy: '''''Hyah!'''''

:[As Cueball watches, Beret Guy floats on top of the invisible giant dog about a meter above the two small dogs, and then rides away with the two small dogs still seen below as they run to the right, leaving Cueball standing in the dust the "big" dog creates in its wake. The invisible giant dog barks from a position just in front of Beret Guy's face, far above the two small dogs.]
:Invisible giant dog: <big>'''''WOOF'''''</big>
:Beret Guy: ''Away!''

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Beret Guy]]
[[Category:Strange powers of Beret Guy]]
[[Category:Astronomy]]
[[Category:Physics]]
[[Category:Animals]]
[[Category:Dogs]]

1342: Ancient Stars

2022-05-04T19:54:52Z

172.70.110.121: Undo revision 241954 by Ex Kay Cee Dee (talk)

{{comic
| number = 1342
| date = March 14, 2014
| title = Ancient Stars
| image = ancient_stars.png
| titletext = 'The light from those millions of stars you see is probably many thousands of years old' is a rare example of laypeople substantially OVERestimating astronomical numbers.
}}

==Explanation==
[[Cueball]] makes the common observation that many of the visible stars in the sky are so distant that it takes thousands of years for light from that star to reach Earth. However, the brightest star {{W|Sirius}} is one of the nearest at a mere 8.6 {{W|Light-year|light-years}} distance. In other words, the light that was arriving from Sirius in March 2014, when the comic was posted, was emitted some time around August 2005. The previous US president, {{W|George W. Bush}}, was in office from 2001 to 2009 and [[Megan]] notes that this isn't a terribly impressive observation.

The title text references the fact that most normal people have a hard time imagining the large scale of astronomical numbers. For example, the distance between astronomical bodies or the size of the Sun are hard to imagine; they typically underestimate them by many orders of magnitude and think they are much smaller than they actually are. See {{tvtropes|SciFiWritersHaveNoSenseOfScale|Sci-Fi Writers Have No Sense of Scale}}

In this case, however, people instead overestimate both the number of visible stars and their distance by quite a bit. It's frequently cited that about 5,000 to 10,000 stars are visible in the sky by the naked eye. The {{W|Bright Star Catalogue}} is a star catalogue that lists all stars of {{W|apparent magnitude}} 6.5 or brighter, which is roughly every star visible to the naked eye from Earth. The catalog contains 9,110 objects, of which 9,096 are stars, ten are {{w|Nova|novae}} or {{w|supernovae}}, and four objects outside of our Milky Way (two {{w|globular cluster}}s and two {{w|open cluster}}s). To see most of these you need good eyes and a very dark night, and at any point you will only be able to see fewer than half of these as the rest are blocked by the Earth.

This list shows the {{W|Visible stars|91 brightest stars}}. Of these 59 are more than 100 light years away and only 6 are more than 1,000 light years away. The farthest on this list, {{W|Eta Canis Majoris|Aludra}}, is "only" 3,200 light years away. Our entire {{w|Milky Way}} contains up to 400 billion (400x10⁹) stars and has a diameter of 100,000 light years.

There are visible objects much farther away, like the {{w|Andromeda Galaxy}} which is 2.5 million light years away and made up of billions of stars. And a gamma ray burst {{w|GRB 080319B}} would have been briefly visible to the naked eye, despite being 7.5 billion light years distant.

See also [[1212: Interstellar Memes]], [[1644: Stargazing]].

==Transcript==
:All of the panels of this comic are white-on-black.

:[Megan and Cueball stand facing each other, looking up at the sky.]
:Cueball: Just think - the light from that star was emitted thousands of years ago. It could be long gone.

:[Cueball looks at Megan, who is still looking up.]
:Megan: That's Sirius. It's eight light-years away.

:[Cueball looks up again.]
:Cueball: Oh.

:[Both look at one another.]
:Cueball: Just think - the light from that star was emitted in the previous presidential administration.
:Megan: Hmm, doesn't pack quite the punch.

==Trivia==
*The star {{W|List of stars in Cassiopeia|V762 Cas}} in the {{W|Cassiopeia (constellation)|Cassiopeia constellation}} is listed as being 14818 light years away and still having an {{W|apparent magnitude}} of 5.87 - thus being within the visible 6.5 limit. If Cueball had been able to point this star out, he would have been correct. But it is only visible under perfect conditions.

{{comic discussion}}
[[Category:Comics with inverted brightness]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Astronomy]]

855: 1999

2022-05-04T19:53:44Z

172.70.110.121: Undo revision 241981 by Ex Kay Cee Dee (talk)

<noinclude>:''This page refers to the comic named "1999". For comic #1999, see [[1999: Selection Effect]].''</noinclude>
{{comic
| number = 855
| date = February 2, 2011
| title = 1999
| image = 1999.png
| titletext = 'Whoa, twenty-two in two hours!' 'Your site got twenty-two hundred hits in two hours?' 'No. Twenty-two. But still, that's like half the people on the internet!'
}}

==Explanation==
This comic is a parody of the movie ''{{w|The Social Network}}'', a movie about the founding of the popular social network site Facebook. Here, scenes from the movie are reimagined to feature {{w|Zombo.com}} instead. Zombo.com, also known as Zombocom, is a website that was created in 1999 and using only {{w|Flash animations}}. The animation consists of a circle of quickly pulsating dots and a friendly deep male voice repeatedly welcoming the visitor to "Zombocom" and explaining that there was no limit to what could be done at the site, or rather, no limit except yourself. The message repeats while, ironically, there is absolutely nothing that can be done at the site until the message completes, at which point a link saying "Sign up for our newZletter" appears, linking to a page saying that the selected option is not available yet. If the link is not clicked, the Flash player will reset. Thus, you can still do nothing on the site.
The humor of the parody comes in substituting Facebook, a site that, at the time this comic was made, was a useful and popular website; for Zombo.com, a novelty site which gained attention for its complete uselessness.

You can visit the site at [https://zombo.com zombo.com].

The last four panels are all direct parodies of specific scenes from ''The Social Network''. The second panel is a takeoff of the scene where Facebook founder Mark Zuckerberg comes up with the idea for the site, saying that people like checking up on their friends and acquaintances, so why not build a site that lets them do that? Because Zombo.com has no actual function, in this version the founder can't specify what he wants the site to do.

The third panel is taken from a scene where Zuckerberg is seen intensely focused on programming the site, his headphones insulating him from the outside world. His assistant describes his state as "wired in" and demands that he not be disturbed. In the comic, as Zombo.com is a very simple site which does not need much coding, the assistant offers the possibility that the founder is stoned. Indeed, it's one of the few conceivable reasons that one would be this focused on such a useless website. As "the infinite is possible" is a phrase in Zombo.com's audio clip, it is also plausible that the founder is currently recording the clip, and the assistant is telling the others not to bother him for fear of adding background noise to the clip.

The fourth panel is taken from a scene where co-founder Eduardo Saverin tries to push for monetization of Facebook, while investor and consultant Sean Parker argues against. The actual dialogue is "You don't even know what the thing is yet. How big it can get, how far it can go. This is no time to take your chips down. A million dollars isn't cool, you know what's cool? A billion dollars." Here, instead of a billion dollars, the Parker character argues "Circles," playing off Zombo.com's un-lucrative nature and the silliness of the design.

The final panel is taken from a scene where Parker advises Zuckerberg to change the name of the site from TheFacebook to just Facebook, calling it "cleaner." Here, he advises to change the name of Zombo.com to just Zombocom. Why the website is pronounced "Zombocom" rather than the more expected Zombo ''Dot'' Com is a mystery known only to its creators; perhaps, like in the movie, they also considered it cleaner.

The title text is a reference to a quote from the movie, specifically a conversation between Zuckerberg and Delpy (Zuckerberg is the first quote). In the actual film, Zuckerberg answers "twenty-two thousand" rather than just "twenty-two". This is a joke to the effect that, back in 1999, there weren't really that many people on the internet, and very few of them would have gone to Zombo.com.

==Transcript==
:It's easy to forget, as we heap awards on ''The Social Network'',
:That before there was Facebook, MySpace, or even Friendster...
:One website dreamed bigger than them all.

:[Cueball and another are talking.]
:Cueball: People like doing stuff. So why not build a website that offers that?
:Another: Offers what? What would I do there?
:Cueball: Anything! The only limit is yourself!

:[Another scene. Hacker, wearing headphones and oblivious, working at computer. Cueball runs in to interrupt; Another holds him back.]
:Cueball: Hey, we need more—
:Another: Don't–he's wired in.
:Hacker: ''The infinite is possible.''
:Another: Or baked. It's hard to tell.

:[Cueball and another at table in bar.]
:Cueball: It's time to monetize. We could make millions!
:Another: No way. A million dollars isn't cool. You know what's cool?
:Cueball: A billio–
:Another: ''Circles.''

:[Long shot in bar. Drinks on table in foreground; dim figures in doorway in background; Cueball, alone, shouting into the distance.]
:Cueball: Hey–a tip: drop the dot.
:Cueball: Just "Zombocom".
:Cueball: It's cleaner.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics with inverted brightness]]
[[Category:Internet]]
[[Category:Social networking]]
[[Category:Multiple Cueballs]]

705: Devotion to Duty

2022-05-04T02:03:43Z

172.70.110.121: Undo revision 233382 by X. K. C. D. (talk)

{{comic
| number = 705
| date = February 22, 2010
| title = Devotion to Duty
| image = devotion_to_duty.png
| titletext = The weird sense of duty really good sysadmins have can border on the sociopathic, but it's nice to know that it stands between the forces of darkness and your cat blog's servers.
}}

==Explanation==
In this comic, we see a man talking on a phone. We are unsure of his aims (terrorism, robbery, etc.) but he has taken hostages and cut all links to the outside world, in order to control the situation and prevent the police from observing the interior of the building (as popularly depicted in film and television). Initially, the villains seem to have everything under their control, but then the hostage-taker explains on the phone that someone has entered the building, climbed the air vents to bypass their cordon, effortlessly killing other hostage-takers (who are likely hardened killers with weaponry) on his way to the server room and then ignored the hostages, preferring instead to reconnect the servers to the outside world. The hostage-taker is evidently puzzled by this and explains it to the person on the other end of the phone, who immediately recognizes the reason: the man that entered the building is a sysadmin (short for {{w|system administrator}}), and he is concerned that his servers are losing uptime (time spent running or connected to the internet). This evidently concerns the man on the phone, who knows that a good sysadmin is an unstoppable force once started!

This comic is a reference to one of two things (or both): the Hollywood depiction of heroes able to perform superhuman feats in tricky situations (such as John McClane in ''{{w|Die Hard}}'', which the first two panels are a deliberate reference to), or the duty that people impose upon themselves to go above and beyond the call of duty to ensure that they carry out their work (in this case a dutiful sysadmin, concerned for those trying to use his server).

The title text is a simple joke about the fact that the sysadmin will crawl through broken glass and defeat criminals/terrorists (forces of darkness) just so a cat blog (where owners write about their cats) can stay up. This creates a humorous contrast between the seriousness with which large websites treat issues like uptime and business continuity and the often mundane and banal uses people actually have for them.

A sysadmin is also mentioned in the title text of [[309: Shopping Teams]].

==Transcript==
:[Bearded criminal is holding a pistol and talking on a mobile phone.]
:Criminal: We took the hostages, secured the building and cut the communication lines like you said.
:Phone: Excellent.

:[Still talking on the phone, waving gun around in the air animatedly.]
:Criminal: But then this guy climbed up the ventilation ducts and walked across broken glass, killing anyone we sent to stop him.

:Phone: And he rescued the hostages?

:[Criminal looking confused and defeated, shoulders hunched and pistol hanging limply at his side.]
:Criminal: No, he ignored them. He just reconnected the cables we cut, muttering something about "uptime".
:Phone: Shit, we're dealing with a ''sysadmin''.

==Trivia==
This comic was made into [http://store.xkcd.com/collections/apparel/products/sysadmin a shirt] in the xkcd store, which includes a new illustration on the back.

{{comic discussion}}

[[Category:Computers]]
[[Category:Comics with xkcd store products]]

2182: When I'm Back at a Keyboard

2022-05-04T02:03:31Z

172.70.110.121: Undo revision 234025 by X. K. C. D. (talk)

{{comic
| number = 2182
| date = July 29, 2019
| title = When I'm Back at a Keyboard
| image = when_im_back_at_a_keyboard.png
| titletext = [after typing 1,500 words on feathered dinosaurs, paleontology, sexism, lava, and dinosaurs as animals rather than movie monsters] Sorry to cut it short, I'm on my phone. When I'm back at a keyboard, I can give you another 5,000 words.
}}

==Explanation==
[[Cueball]] is texting someone on his phone. However, since with a {{w|Computer keyboard|full sized physical keyboard}} you can type with all of your fingers, which is usually a much faster and more accurate way than using an on-screen keyboard on a smartphone, Cueball cuts off the conversation and says he will get back to whoever he was talking to when he can type on an actual keyboard, presumably at home and on his computer. While there are multiple techniques for making a smartphone increasingly easier to enter words into using its on-screen {{w|virtual keyboard}}, such as keyboard swiping, on-the-fly spelling and grammar checkers, and voice recognition to minimize using the keyboard at all, the combination of a full-sized keyboard along with a generous sized screen is hard to beat for speed and accuracy when typing larger blocks of text.

The joke is that despite claiming to be more proficient with a physical keyboard, rather than a digital one, [[Randall]] still {{tvtropes|BerserkButton|goes into long rants}} through messages on his smartphone, whenever anybody brings up ''{{w|Jurassic Park}}''.

There might also be a reference on Dennis Nedry, a character from the first ''Jurassic Park'' film. The programmer is responsible for a security sabotage and intends to be away from his keyboard only for a short while, but dies (not altogether) unexpectedly, worsening the situation in the park.

The title text shows a typical sentence from Randall after having been in a chat over his phone. Before the sentence he has written 1500 words on his phone, all related to Jurassic Park, more or less. When he finally have written his fingers off he then says that he will have to stop now but once back at a keyboard, and even though he just typed 1500 words on his phone, he is ready to type even more (5000 words) using his keyboard.

The widespread uptake of mobile devices has stark implications for {{w|user-generated content}} sites on the internet. According to [https://www.nytimes.com/2014/02/10/technology/wikipedia-vs-the-small-screen.html a 2014 ''New York Times'' article,] only one percent of the changes to Wikipedia articles were made via mobile devices, although they displayed about a third of all Wikipedia page views that year.

==Transcript==
:[Cueball is walking while holding his phone in both hands. A line from the screen on the phone goes to the text above him, indicating what he writes:]
:Cueball (texting): Sure, I can reply once I'm back at a keyboard and can type more easily.

:[Caption below the panel:]
:I say this a lot for someone who routinely types thousands of words in text message conversations when someone brings up ''Jurassic Park''.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Jurassic Park]]
[[Category:Smartphones]]

1924: Solar Panels

2022-05-04T02:03:21Z

172.70.110.121: Undo revision 232870 by X. K. C. D. (talk)

{{comic
| number = 1924
| date = December 4, 2017
| title = Solar Panels
| image = solar_panels.png
| titletext = This works for a surprising range of sunlit things, including rooftops (sure), highway surfaces (probably not), sailboats (maybe), and jets, cars, and wild deer (haha good luck).
}}

==Explanation==

This handy decision tree aims to help in finding out whether a given object should have {{w|solar panel}}s installed on it.

The root question is whether the object of choice moves. If it doesn't and has no nearby empty space that would be more practical for the solar panel installation, then yes, the object should be equipped with the solar panels. If the object is static, but you could more easily install the panels somewhere else nearby, probably that's the best place. An example of this is a slanted rooftop of a house or a field on a hillside: it's certainly possible to put solar panels there, but if a flat surface, like a flat-roofed house or a level field, is available, it would generally be easier to put them on that. This way, you can select the optimal direction for the panels to face, which might not be possible on a given incline, or even have them [https://www.linak.com/business-areas/energy move to track the sun]. However, if the house has a side that is turned towards the sun (south in the Northern hemisphere) then a house roof could be even better than on the ground, which is why the title text says "sure" for rooftops. For another example of things where "putting next to it" instead of "on it" is generally the easier (and arguably better) option, see the "highway surfaces" of the title text.

If the object moves, the next question is whether its batteries can be recharged or swapped with ease, in which case batteries may be a better option than solar panels, if the purpose of the panels is to power the object. The idea is that solar panels on a vehicle sound like an interesting idea, but batteries can be much more easily (and economically) recharged from a fixed electrical station than using solar panels on the vehicle as a power source. It may be possible to have solar panels ''on the electrical station'', but that is a separate device to consult the table on.

Finally, if the object moves and batteries are not an option, the last question is whether the object heats up during operation. If so, solar panels may not work well. [[Randall]] doubts it mockingly, see also the title text regarding his ''Haha Good luck'' final option.
Solar panels can only produce electrical power equal to about 20% of the solar radiation they receive. Thus, a device that heats up during use likely consumes much more power than the amount which could be produced by solar panels covering its surface - so "good luck". Obviously, many animals are also "moving objects" fitting this condition, and installing solar panels on them is bound to be a challenge.
Moreover, solar panels do not work effectively when excessively hot [http://news.energysage.com/solar-panel-temperature-overheating/] (solar panels are typically designed to operate in temperature ranges of 15-25 Celsius, 59-77 Fahrenheit, 288.15-298.15 Kelvin, 518.67-536.67 Rankine, 12-20 Réaumur, 15.38-20.63 Rømer, 127.5-112.5 Delisle, 4.95-8.25 Newton, 5.968 546×10⁻²¹ - 6.174 608×10⁻²¹ [[2292: Thermometer|joules of translational kinetic energy]] or 37-51 [[1923: Felsius|Felsius]]).

But if changing batteries is not an option, and heat production and power requirements are low, then solar panels can be an excellent solution on a moving object. An excellent case for this is on [[:Category:Space probes|space probes]] and satellites, which are typically powered entirely by solar panels (and reliably receive sunlight, because there are no clouds to interfere). Randall is well aware of this, as shown with the comics [[695: Spirit]] and [[1504: Opportunity]] about the two solar-powered [[:Category:Mars rovers|Mars rovers]], although in this comic he seems to have only been concerned with Earthbound objects.

The flow chart, however, does not mention if the thing in question actually ''needs'' solar panels, but according to the title text it works very well, and thus Randall implies that if the answer is ''sure'' then it is relevant to put solar panels there. The more solar panels in place, the fewer fossil fuels are needed, and this is in line with Randall's general interest in reducing [[:Category:Climate change|climate change]].

The title text suggests that this flow chart is very broadly applicable to anything the Sun hits.

Rooftops are classed as "sure", and those are, indeed, an active subject of solar installation (though, if there's suitable land nearby, it might not be the most efficient).

Highway surfaces are classed as "probably not". There have been proposals and experiments a concerning {{w|photovoltaic pavement covering roadways with solar panels}}, but these have proven to be impractically expensive and prone to damage. The flow chart suggests that, since many highways are near land that could be used for solar panels, that will usually be the more viable option.

Sailboats are classed as "maybe". Unlike boats with motors, sailboats don't consume enough power to heat up, only requiring enough power to provide electricity for whatever equipment and appliances are on board. Since some sailboats are at sea long enough that swapping or recharging batteries may be difficult, solar panels could be a viable option.

Multiple other moving objects, including jets, cars, and wild deer ends up on the ''haha good luck'' result. While these examples seem unrelated, they all have the same limitation: they consume far more power while moving than could realistically be harnessed from solar panels (as demonstrated by the fact that they noticeably heat up). There are some experimental solar-powered cars, but these tend to be exceptionally low power (and resultingly low-performance) vehicles. Wild deer are clearly a humorous option, as they'd have little use for the electricity from solar panels, and would likely resist any efforts to install them. Nonetheless, Randall includes them to make the point that the chart is effective, even with ridiculous examples.

==Transcript==

:[A flow chart that features four questions in bubbles. Each question has yes/no options in bubbles overlain to the left and right on the question bubble. Curved arrows points from the yes and no bubbles to either the next question or the result. The result written at the bottom is not inside bubbles. The chart has two main branches, that ends up in five places using only four different results, as the middle result is shared by both branches. Above the chart, there is a caption:]
:'''Should I put solar panels on it?'''

:Does it move around?
::Yes
:::Does it have regular chances to recharge or swap batteries?
::::Yes
:::::Probably not
::::No
:::::When running, is it hot to the touch?
::::::No
:::::::Maybe
::::::Yes
:::::::Haha good luck
::No
:::Is there an empty space nearby where it would be easier to put them?
::::Yes
:::::Probably not [Uses the same sentence as the one in the first branch.]
::::No
:::::Sure

{{comic discussion}}

[[Category:Flowcharts]]
[[Category:Animals]]
[[Category:Solar power]]

1236: Seashell

2022-05-04T02:03:10Z

172.70.110.121: Undo revision 235052 by X. K. C. D. (talk)

{{comic
| number = 1236
| date = July 10, 2013
| title = Seashell
| image = seashell.png
| titletext = This is roughly equivalent to 'number of times I've picked up a seashell at the ocean' / 'number of times I've picked up a seashell', which in my case is pretty close to 1, and gets much closer if we're considering only times I didn't put it to my ear.
}}

==Explanation==
This method of relating the probabilities of two events is known as {{w|Bayes' theorem|Bayes' Theorem}}.

{{w|If}} you put a {{w|seashell}} up to your ear, you might hear {{w|Seashell resonance|a sound similar to the ocean}} apparently inside the shell. But the idea that this sound is actually the sound of the sea is just a popular myth: hold only your hands close to your ears and you will hear the same sound, as it is the sound of your blood moving through your blood vessels that causes the sound. The comic, through an application of Bayes' Theorem, points out that most of the time when you pick up a seashell, you are in fact at the beach next to the real ocean, so hearing the ocean at that location is not all that impressive, but it's just real.

The equation should, however, be read as follows: (The probability that I'm near the ocean, given that I picked up a seashell) is equal to (The probability that I picked up a seashell, given that I'm near the ocean) multiplied by (The probability that I'm near the ocean) divided by (The probability that I picked up a seashell).

The title text points out that most instances where the author has picked up a seashell have been at the beach, and nearly all of the times where he has picked up a seashell and not put it to his ear have been there.

This comic was released late. In the first version, the formula was incorrect, but it has since been corrected.

==Transcript==
:[At the top of the panel is an equation showing Bayes' Theorem for the probability that a person is near the ocean given that they just picked up a seashell.]

:P(I'm near the ocean|I picked up a seashell) =

:P(I picked up a seashell|I'm near the ocean)P(I'm near the ocean)
:------------------------------------------------------------------------------------------------
:P(I picked up a seashell)

:[The probability that I'm near the ocean given I picked up a seashell equals the probability I picked up a seashell given I'm near the ocean times the probability I'm near the ocean all divided by the probability I picked up a seashell.]

:[Cueball holds a seashell and stands to the left of the panel, to the right, a few birds are flying around and the sound of a wave crashing against the shore is depicted.]
:''Crashhh'' ''Sploosh''

:Statistically speaking, if you pick up a seashell and ''don't'' hold it to your ear, you can probably hear the ocean.

==Trivia==
Note that while this form of Bayes's theorem is often taught in statistics classes, [https://www.springer.com/gp/book/9783319397559 at least one statistician] tries to show in a philosophical way that unconditional probability does not exist, which would make the equation improper as stated.

{{Comic discussion}}
[[Category:Math]]
[[Category:Statistics]]
[[Category:Comics featuring Cueball]]

773: University Website

2022-05-04T02:02:59Z

172.70.110.121: Undo revision 235481 by X. K. C. D. (talk)

{{comic
| number = 773
| date = July 30, 2010
| title = University Website
| image = university website.png
| titletext = People go to the website because they can't wait for the next alumni magazine, right? What do you mean, you want a campus map? One of our students made one as a CS class project back in '01! You can click to zoom and everything!
}}

==Explanation==
This comic uses a Venn diagram to point out that there is often a significant disparity between what a university displays on the front page of its website and what users — particularly prospective students — are primarily interested in finding there.

This is often because those who are making the university website instinctively believe, from their perspective, that the website should contain things that the university is proud of, or that they personally find useful, so they are unable to look at it from the perspective of a person who is new on campus and simply wants to know what number to call for campus security. Thus, simple details like contact information and university data are often overlooked.

The title text presents a satirical response from the school defending their site design, consisting mostly of PR worthy of an alumni magazine (a publication that is seldom anticipated so eagerly). It also uses sarcasm to make fun of university websites that have wildly out of date site design (web technology was relatively primitive in 2001 {{Citation needed}}) and a CS (Computer Science) student built it instead of a professional.

==Transcript==
:[A venn diagram.]
:[The left circle is labeled "Things on the front page of a university website" and contains:]
:"campus photo slideshow"
:"alumni in the news"
:"promotions for campus events"
:"press releases"
:"statement of the school's philosophy"
:"letter from the president"
:"virtual tour"

:[The right circle is labeled "Things people go to the site looking for" and contains:]
:"list of faculty phone numbers and emails"
:"campus address"
:"application forms"
:"academic calendar"
:"campus police phone number"
:"department course lists"
:"parking information"
:"usable campus map"

:[The only item in the overlapping section is:]
:"full name of school"

==Trivia==
*Some university administrators reportedly took this cartoon to heart. For further discussion of this cartoon, see [http://www.insidehighered.com/news/2010/08/04/no-laughing-matter Inside Higher Ed], [http://dylanwilbanks.com/blog/2010/07/30/this-is-my-truth-tell-me-yours/ DylanWilbanks.com], and [http://convergeconsulting.org/eduguru/2010/08/redesign-your-university-website-according-xkcd/ .eduGuru].
*The University of Arizona created an ''unofficial'' page at [http://at.arizona.edu http://at.arizona.edu] to become compliant to this comic and also links to [[xkcd]]. Try to find all that information at their ''official'' home page at [http://www.arizona.edu http://www.arizona.edu].

{{comic discussion}}
[[Category:Internet]]
[[Category:Venn diagrams]]

2477: Alien Visitors

2022-05-04T02:02:49Z

172.70.110.121: Undo revision 232934 by X. K. C. D. (talk)

{{comic
| number = 2477
| date = June 16, 2021
| title = Alien Visitors
| image = alien_visitors.png
| titletext = Stay right there, we'll be back in a minute. We've just gotta brainstorm some new wonders. Have you all figured out gears yet? Yes? Crap.
}}

==Explanation==
This is the first comic in a [[:Category:Alien Visitors|new series]], followed in the next comic by [[2478: Alien Visitors 2]].

This strip satirizes the {{w|ancient astronauts}} hypothesis: that {{w|Extraterrestrial life|aliens}} were involved in building the {{w|pyramids}} and {{w|Stonehenge}}. This concept, popular in some circles, is based on the assumption that earlier civilizations lacked the technology to build such large structures. There are also geometric or other scientific properties to these structures, which some people assume that humans of that era would have been incapable of creating. {{w|Erich von Däniken}}, a Swiss author, is one of the foremost proponents of "ancient astronauts." Some say that such pseudoscience is inherently racist, as it assumes, without any proof, that other civilizations were unable to build their monuments without foreign help. Although others disagree since most races and nationalities have one or another of these monuments with similar claims.

In the comic, aliens arrive with the intention of building such monuments with their highly advanced technology, including some sort of tractor beam to lift the heavy stones and another beam that can depict a pyramid. They are shocked to hear from [[Cueball]] that humans accomplished the same thing thousands of years earlier with such simple tools as ramps, and even in more than one location on Earth (Pyramids in {{w|Egyptian pyramids|Egypt}} and {{w|Mesoamerican pyramids|Mexico}}). Thus they proceed to suggest a stone circle to predict the solstice, but before they can finish this sentence [[Megan]] says this is like Stonehenge.

The joke of the strip is that, if aliens were interested in building such structures on earth, they'd be just as likely to show up today as thousands of years ago. And if they offered to build pyramids today, humans would be very unimpressed, as we've had the technology to do so for quite some time. The notion that an advanced, spacefaring species would come all the way to Earth (or whatever other planets they visit) to build relatively simple stone structures seems dubious, when put that way.

Alternately, the aliens may have visited Earth before in the past and impressed the humans of the time with their advanced technology of pyramids and stone circles, leading them to expect the same technology to impress the humans again in the present day. This is somewhat plausible: Stonehenge is estimated to have been built around 3100BC, while the pyramids were built 500-1000 years later. Assuming both structures were indeed built by aliens in the past, the visitors would have returned to the Earth to find agricultural civilizations almost identical to the ones they encountered centuries prior. The aliens could have then been led to believe that human technology, if almost entirely unchanged in the 500 years since they last visited, would not have advanced significantly in a few thousand years. Indeed, the aliens were mostly correct in this assessment: technological advancement progressed at a crawl until the scientific revolution marked the emergence of modern science only a relatively short 600 years ago. From this perspective, the aliens would seem to be correct in their assumption that human technology would not significantly improve such that they could not impress humanity with their technological wonders. Unfortunately, the aliens have been caught off-guard by the exponential nature of technological advancement, in that advanced civilizations have the resources to advance even more rapidly.

The aliens' reaction is frustration as they cannot teach us anything new; evidently, it does not occur to them to share their technologies for {{w|antigravity}} and {{w|interstellar travel}} (which, having come to Earth in floating spaceships, they clearly possess).

In the title text they have regrouped and would now present another wonder - {{w|gears}}. This is very likely a reference to the {{w|Antikythera mechanism}}, an artifact dating from the 2nd century BC which used a complex, geared calculating system to predict the movement of stars and planets. As with the aforementioned structures, some fringe groups theorize that such mechanisms were beyond human technology at the time, and therefore must have been given by aliens. Once again, such technology is not impressive to humans at this point, as complex, geared mechanisms are now commonplace in most human societies. Indeed, quite a bit of intricate mechanical gearing and timing has been obsoleted by electronics.

==Transcript==
:[A flying saucer is hovering high above Cueball and Megan, drawn very small standing on the ground beneath it. The aliens inside speak to them from inside their saucer, indicated with zigzag lines between it and the text.]
:Aliens: Greetings, humans!
:Megan: Whoa, aliens!
:Aliens: We bring you technological wonders!

:[Zoom in on the flying saucer which has two beams below it, the left showing an outline of a pyramid and the right is shown lifting a large stone. Cueball replies off-panel.]
:Aliens: We will help you lift great stones and build towering monuments.
:Cueball (off-panel): Oh, pyramids?

:[Zoom in on Cueball and Megan looking up, the Aliens reply from above the panel.]
:Aliens (off-panel): ...Yes.
:Cueball: Yeah, we have those. In Egypt.
:Megan: And Mexico.
:Cueball: I think they used ramps?

:[Zoom back out, as in first panel]
:Aliens: Then we shall build a ring of stones aligned with the stars, so at the solstice-
:Megan: Oh, like Stonehenge?
:Aliens: ''Dammit, humans.''

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Aliens]]
[[Category:Alien Visitors]]
[[Category:Comics sharing name|Alien Visitors 1]]

2241: Brussels Sprouts Mandela Effect

2022-05-04T02:02:38Z

172.70.110.121: Undo revision 234949 by X. K. C. D. (talk)

{{comic
| number = 2241
| date = December 13, 2019
| title = Brussels Sprouts Mandela Effect
| image = brussels_sprouts_mandela_effect.png
| titletext = I love Brussels Sprouts Mandela Effect; I saw them open for Correct Horse Battery Staple.
}}

==Explanation==
{{w|Brussels sprouts}} are a leafy vegetable from the cabbage family which were cultivated in Brussels, in what is now Belgium, in the 13th century, giving them their name. Many adults and children [https://www.camdenliving.com/blog/why-do-we-hate-brussel-sprout dislike Brussels sprouts], perhaps because of their bitterness.

[[Cueball]] was one of these people who thought he had a dislike for Brussels sprouts, but after trying them recently he had a change of heart and likes them now. He feels "misled" by the public dislike for Brussels sprouts. [[Megan]] chimes in and notes that it is not just him. Farmers started to develop a newer {{w|cultivar}} of Brussels sprouts in the 1990s (as opposed to the 15 years ago referenced in the comic), which taste less bitter than the "original" cultivar of Brussels sprouts that Cueball grew up eating. (A [https://npr.org/773457637 source] is provided in the comic as a foot note to Megan's statement. This would be the first of two comics in a row with this type of reference given, the second coming in [[2242: Ground vs Air]].)

It seems that others have also started to like Brussels sprouts, which Megan calls a real {{w|False_memory#Mandela_Effect|Mandela Effect}}, hence the title ''Brussels Sprouts Mandela Effect''. Megan explains that now the whole world have a "false" shared memory of Brussels sprouts tasting bad, and it is like we have all switched to the parallel universe where they taste good. This idea was earlier used in [[1268: Alternate Universe]] regarding the weird idea of eating lobsters.

{{w|false memory|False memories}} may arise via suggestibility, activation of associated information, the incorporation of misinformation, and source misattribution, and {{w|False_memory#Commonly_held_false_memories|they can be shared}}, sometimes widely, when one of these triggers happens to many people in a population.

The Mandela Effect, however, is a pseudoscience explanation for a false memory shared by multiple people. It proposes that the false memory is actually real, but the people who share it somehow experienced it in a parallel world, or that reality somehow around them changed in some way, while their memories remained intact. This is why Megan calls this a real Mandela effect, because in this situation it is the world we live in that has actually changed, not our memories that are wrong. Now the Brussels sprouts taste different than we remembered, it is not our memories that are wrong.

In the last panel, [[Ponytail]] then tricks Cueball into thinking that {{w|licorice}}, [https://www.nbcnews.com/healthmain/why-do-so-many-us-hate-black-licorice-few-theories-963738 another widely disliked food], is good tasting. At this point Megan realizes that this must be a trap. Unlike Brussels sprouts, the taste of licorice has not changed noticeably, so people who hated the taste before are likely to still find it unpleasant.

That Ponytail is up to no good is shown to be true when she additionally claims that {{w|Silica_gel|silica gel}} packets are actually edible and taste delicious. This is very false! {{w|Silica_gel#Desiccant|Silica gel packets}} are typically used as a desiccant, to keep electronics and other moisture sensitive items dry. They are typically marked "[https://www.123rf.com/photo_72752039_single-silica-gel-packet-isolated-on-white-background-.html Do Not Eat]" to warn people that they are not edible. Although not toxic, and even {{w|Silica_gel#Food_additive|allowed in some form in food}}, silica gel has a sand-like texture and no flavor or nutritional value, can {{w|Silica_gel#Hazards|cause irritation}} if digested in the raw form, and the packets may contain {{w|Silica_gel#Humidity_indicator_(blue/orange_silica_gel)|potentially toxic additives}}.

Cueball, having been prepped by both his own experience and Megan's facts are totally ready to believe Ponytail, even to the extent that he seems to feel cheated by the makers of silica gel packets, who he must now think has written ''Do Not Eat'' just to keep that delicious gel for themselves. Hopefully Megan can convince him not to find and eat them. Ponytail is often not nice to Cueball, although in other comics it is more like she talks him down, see [[:Category:Code Quality|Code Quality]], not directly trying to harm him.

The title text suggests that "Brussels Sprouts Mandela Effect" is a music band, who once were the {{w|opening act}} for the presumably better known band "Correct Horse Battery Staple". This latter group is a reference to [[936: Password Strength]]. It hints at the "{{tvtropes|AGoodNameForARockBand|good name for a musical band}}" trope, which Randall before tried to replace by a dot tumblr dot com trope in [[1025: Tumblr]]. Indirectly, he also suggests that ''Brussels Sprouts Mandela Effect'' would be a great long password that is now easy to remember (as long as you remember [https://www.reddit.com/r/MandelaEffect/comments/6meq1a/brussel_sprouts_right/ there is an S] at the end of {{w|Brussels}} (at least in English, but not in Dutch, which is one of the official languages of Brussels/Belgium)).

For a comic about awkwardly named bands, see [[119: Worst Band Name Ever]].

==Transcript==
:[Cueball is standing between Ponytail and Megan talking to them.]
:Cueball: I always thought of Brussels sprouts as terrible, but they're actually really good! I can't believe I let everyone mislead me!

:[In a frame-less panel Megan replies. Below her is a footnote with a citation to back up her statement.]
:Megan: It's not just you! Farmers developed a less-bitter cultivar like 15 years ago.*
:*npr.org/773457637

:[Back to all three as Megan continues to explain while holding her arms away from her.]
:Megan: Now the whole world is having this revelation, one person at a time. It's like a real Mandela effect. We secretly switched to the parallel universe where Brussels sprouts taste good.
:Cueball: ''Cool.''

:[Ponytail lifts a finger as Cueball and Megan turns to look at her.]
:Ponytail: Also, licorice is good now.
:Cueball: Whoa, really?
:Megan: This is a trap.
:Ponytail: And those silica gel packets that say "Do not eat"? '''''Delicious.'''''
:Cueball: ''I knew it.''

==Trivia==
* The URL given was [https://www.explainxkcd.com/wiki/images/archive/5/5d/20191216154116%21brussels_sprouts_mandela_effect.png originally] given [https://npr.org/773457633 npr.org/77345763'''3'''] but this was an error!
**The actual URL is number 77345763'''7''' which was later corrected by an updated comic.
**Here is the [https://text.npr.org/s.php?sId=773457637 plain HTML version] and here the [https://npr.org/773457637 full site].
*As always when Randall offers his opinion on some sort of food, it may lead to [[388:_Fuck_Grapefruit#Controversy|controversy]] and lots of discussion in the [[Talk:2241:_Brussels_Sprouts_Mandela_Effect|talk page]].

{{comic discussion}}

[[Category: Comics featuring Cueball]]
[[Category: Comics featuring Megan]]
[[Category: Comics featuring Ponytail]]
[[Category: Food]]

2503: Memo Spike Connector

2022-05-04T01:41:42Z

172.70.110.121: Undo revision 235212 by X. K. C. D. (talk)

{{comic
| number = 2503
| date = August 16, 2021
| title = Memo Spike Connector
| image = memo spike connector.png
| titletext = Backward-compatible with many existing cables, and can connect directly to phones or tablets if you press them down hard enough.
| imagesize =
}}

==Explanation==
This is the third installment in the series of [[:Category:Cursed Connectors|Cursed Connectors]] and presents Cursed Connectors #102: The Memo Spike. It follows [[2495: Universal Seat Belt]] (#65) and was followed 9 days later by [[2507: USV-C]] (#280).

The comic depicts a large metal spike with a wire coming from the base. The spike stabs through two other wires, thus creating an electrical connection between the three. As the name suggests, the spike resembles a {{w|Spindle_(stationery)|stationery spindle}}, colloquially known as a spike, called a Memo Spike here by Randall. However, unlike normal spindles, this one has a cable of some kind coming out of it, suggesting this is a hub of some sort.

Spindles are used to temporarily hold paper by "spindling" or impaling the paper onto the spike (as depicted in the comic). They're most known for their use in restaurants as a way to hold bills that have been paid, or traditionally in offices that work with many bits of paper, e.g. with invoices in a finance department or hardcopy in newspaper editing, to prevent accidental disturbance/shuffling, at the expense of a small puncture mark in each sheet so impaled. (This could cause errors in papers with punch-holes that are meant to be read by machines, hence the admonition against "{{w|Punched_card#Do_Not_Fold,_Spindle_or_Mutilate|folding, spindling, and mutilating}}".) In the latter context, the editor might put all the rejected stories onto a spike (rather than into a wastebasket) to prevent them going astray, and this might be the source of the term '{{w|Spike (journalism)|spiked}}'.

The joke of the comic is while any number of non-destructive connection standards exist, a large spike can provide much of the same results: a conductive object that retains a connection of multiple wires in a way that allows electricity to pass through. Indeed, in the early days of Ethernet, {{w|Vampire tap|vampire taps}} were used, essentially spikes that bit into a cable to establish a new branch in the network. Another type of connection which involves piercing the wire is a {{w|Punch-down block|punch-down block}}, a type of {{w|Insulation-displacement_connector|insulation-displacement connector}}, where one or more wires are pushed into a cutting channel instead of onto a spike.

Depending on the type of cable it is also likely to create a short circuit, e.g. by connecting both strands of a twisted pair of strands in a typical Ethernet cable, or the central wire and the sheath of a coaxial cable. In an enterprise environment, this could even happen on a {{w|Power_over_Ethernet|PoE-Connection}}, which actually carry more noticeable amounts of power (up to 25.5W). Even if this is avoided, the single spike may be large enough to mechanically sever a random subset of the finer strands that exist within a multicore cable such as is commonly in use today.

The title text takes this a bit further. It says that it is backwards compatible with many existing cables. This means any cable large enough to be impaled by the spike could be used. Needless to say it will likely not work anyway. It also continues by saying that phones and tablets can also be connected using this method if you press them down hard enough over the spike. Thus if you actually manage to make the spike penetrate the device's coverings to reach the electrical parts, then there is a connection. The implication is that any device or cable can be connected to any other device or cable as a form of universal adapter/splitter/combiner across arbitrary hardware and communications/power standards. In reality, this could be even more dangerous and will surely destroy the phone/tablet either directly or by overloading their cable connection.{{citation needed}} Also be careful not to impale your hand while trying to push the spike through your tablet's screen.

==Transcript==
:[A memo spike is shown (a device also called a Spindle). It is a long spike standing up from a round base plate. A wire is coming in from the left and appears to be hardwired into the spike's base element. Two other wires comes in from the right. Both are firmly impaled down upon the spike, penetrated completely through shortly before their apparently unterminated ends. The end of the impaled wire closest to the base faces out and the details appear to show it to be of some variety of multicore (rather than co-axial) manufacture. The other cable's end is a bit higher and points into the image. Above is a title and below is a label.]
:Cursed Connectors #102
:The Memo Spike

{{comic discussion}}


[[Category:Cursed Connectors]]

2589: Outlet Denier

2022-05-04T01:40:57Z

172.70.110.121: Undo revision 234382 by X. K. C. D. (talk)

{{comic
| number = 2589
| date = March 4, 2022
| title = Outlet Denier
| image = outlet_denier.png
| titletext = There are regularly placed bumps on the underside just the right size to press the rocker switch on the power strip.
}}

==Explanation==
{{incomplete|Created by a BIG CHUNGUS - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This is the fifth installment in the series of [[:Category:Cursed Connectors|Cursed Connectors]] and presents Cursed Connectors #78: The Outlet Denier.

The outlet denier connector in this comic is the large connector to the right. It has a plug on the downward side that is supposed to go into a {{w|power strip}} or other type of outlet. It has two long bars extending up and down off the plug, as well as a D shape on one side with another, slightly less long bar on the other side of the D, that has the cord connected to it. The purpose of the outlet denier is to block access to as many other ports on a power strip as possible, hence the name. It is designed to work with many different types of power strips, such as the standard one displayed in the comic, as well as ones with the sockets rotated 90 degrees (the long bar extending to the cord) and other types of outlets like the triple outlet on the end of many extension cords and two dimensional power strips that extend a couple of outlets left and right as well as up and down (the D shape on the side). The extreme bars to each side may also prevent plugging the Denier into an outlet close to the floor, forcing the user to use a power strip or similar item for it.

There is an example power strip displayed to the left of the outlet denier, used to help explain that the outlet denier is designed to block as many other sockets on a power strip as possible. The power strip is presumably of the type with a {{w|Light_switch#Rocker|rocker switch}} that can turn the entire power bar off. This power bar has five outlets.

Many appliances require transformers or other large components on their power cord. Sometimes these "power bricks" are built around the plug. The comic is making fun of these types of power bricks, as they often block access to other sockets on a power strip or wall outlet. This can be really annoying when you want to plug in many different appliances into a power strip.

Other plugs are deliberately designed to block the other half of a duplex outlet, preventing users from plugging anything else in that could overload the circuit. The comic could be depicting an extreme case of a cumbersome connector shape designed to block an entire power strip, as the appliance connected to it uses so much power that a single extra item plugged into the power strip would cause problems.

The title text says that the outlet denier has bumps on the underside of the long bar that would match up with the location of the rocker switch no matter which outlet of the strip it is plugged into. It's not clear whether this will turn the power switch off or force it always on. But either way, it gets in the way of the user being able to control the power themselves.

If it forces it off, then the Outlet Denier cannot even be used. So to at least assume someone might actually use it, it must force it on. Since there are nothing else that can go into the power strip, it is not that important it it is possible to switch it off though.

==Transcript==
{{incomplete transcript|Needs clarification}}
:[To the left is a power strip with a rocker switch at the top and five outlets, and a connected wire goes from the top off to the left. To the right is the plug that should go into one of the outlets. A curved wire comes from the right and connects to the end of the connector, which is longer than a normal plug. The prongs are visible underneath where the box ends. But instead of ending there, there is a bar horizontal to the first part, which is longer than the power strip itself. There is a D shaped bar attached to this long bar, centred on the middle of the bar. If it was plugged in, the long bar would cover all the other outlets of the power strip.]

:[Text above the image:] Cursed Connectors #78
:[Text below the image:] The outlet denier

{{comic discussion}}

[[Category: Cursed Connectors]]

2613

2022-05-01T05:28:09Z

172.70.110.121: Redirected page to Main Page

#REDIRECT [[Main Page]]

2613

2022-05-01T05:24:20Z

172.70.110.121: Redirected page to Black Hat

#REDIRECT [[Black Hat]]

2613: Bad Map Projection: Madagascator

2022-05-01T05:23:03Z

172.70.110.121: Redirected page to Black Hat

#REDIRECT [[Black Hat]]

2613: Bad Map Projection: Madagascator

2022-05-01T05:22:18Z

172.70.110.121:

{{comic
| number = 2613
| date = April 29, 2022
| title = Bad Map Projection: Madagascator
| image = bad_map_projection_madagascator.png
| titletext = The projection's north pole is in a small lake on the island of Mahé in the Seychelles, which is off the top of the map and larger than the rest of the Earth's land area combined.
}}

==Explanation==
This is another comic in the [[:Category:Bad Map Projections|Bad Map Projections]] series. This time, Randall used the classic {{w|Mercator projection}} but instead of placing the North Pole on top and the South Pole on the bottom it is oriented so that the top is the island of {{w|Mahé, Seychelles|Mahé}}. The map projection is technically a {{w|Oblique Mercator projection}}, with an unusual choice of the cylinder's axis. Since the Mercator projection tends to visually distort areas near the top and bottom of the resulting map, this gives some areas, notably Madagascar, very unusual shapes.

The Mercator projection became the standard projection for world maps during the 1800s because it is ''conformal of normal aspect'': a {{w|rhumb line}} is displayed as a straight line in a Mercator map. During the age of sail, when navigation was performed by compass - this was a very valuable feature, since one could plot a course between two locations by measuring the direction from one to another on the map and then accounting for the difference between the magnetic and actual north poles to determine which rhumb should be taken. In the mid-20th century this trend was {{w|Mercator_projection#Criticism|criticized}} because the distortion towards the north and south poles gave an inaccurate impression of relative sizes. The most common example given of this distortion is that on a Mercator map of the world Greenland looks to have more area than Africa, when in real life Africa covers 14 times that of Greenland. Thus the reference to making Madagascar larger in this projection. Madagascar is a large island off the south east coast of the main African continent, but has only a quarter the coverage of Greenland. Greenland is often listed as the largest island in the world (which excludes continents in their own right, e.g. Australia) followed by New Guinea, Borneo and then Madagascar in fourth place.

Mahé, mentioned in the title text as the north pole's new location, is the largest island in Seychelles, with an area of 60.7 square miles. The claim in the title text, however, that it is "larger than the rest of the Earth's land area combined", is hard to verify when it is not actually displayed in the projection. That is, if you limit yourself to the comic. Clicking on the actual comic will open a website that displays Mercator projections with the North Pole transplanted to various locations, with the location of the one opened set to Mahé. With this, it is possible to see that the island is indeed larger than the rest of the map's land area combined, with a single national park within the island rivalling Africa in size, and eventually reaching a scale of distortion where a road is thicker than Panama. This also reveals that the location of the North Pole, the lake mentioned by Randall, is the Rochon Dam.

===Comparison of actual/mapped areas===
{| class="wikitable sortable"
! Landmass
! Status
! data-sort-type="number"|Actual Area<ref name="act">Major contiguous land areas that should exclude all islands, ''especially'' major ones, '''''especially''''' especially those listed separately</ref> (Millions of Km²)
! data-sort-type="number"|Proportion Land Area
! data-sort-type="number"|Proportion Image Area<ref name="pri">Of only these listed areas listed</ref>
! data-sort-type="number"|Distortion<ref name="dis">NB. Difference between percentages, rather than percentage difference</ref>
|-
| Africa<ref name="suez">Edge at Suez Canal</ref> || data-sort-value="C2"|Continent 2nd largest || 29.7 || 19.95% || 35% || +15.1%
|-
| Eurasia<ref name="suez" /> || data-sort-value="C1"|Continent Largest || 53.4 || 35.83% || 30% || -5.83%
|-
| North America<ref name="pan">Edge at Panama Canal</ref> || data-sort-value="C3"|Continent 3rd largest || 19.3 || 12.96% || 15% || +2.04%
|-
| South America<ref name="pan" /> || data-sort-value="C4"|Continent 4th largest || 17.8 || 11.96% || 7.8% || -4.16%
|-
| Antarctica<ref name="ice">Significant ice-sheets may complicate mapped/actual 'land' areas</ref> || data-sort-value="C5"|Continent 5th largest || 14.2 || 9.53% || 5.3% || -4.23%
|-
| Madagascar || data-sort-value="I04"|Island 4th largest || 0.592 || 0.40% || 2.9% || +2.50%
|-
| Australia || data-sort-value="C7"|Continent Smallest || 7.55 || 5.07% || 2.5% || -2.57%
|-
| Greenland<ref name="ice" /> || data-sort-value="I01"|Island Largest || 2.17 || 1.45% || 0.87% || -0.58%
|-
| Borneo || data-sort-value="I03"|Island 3rd largest || 0.749 || 0.50% || 0.37% || -0.13%
|-
| New Guinea || data-sort-value="I02"|Island 2nd largest || 0.786 || 0.53% || 0.32% || -0.21%
|-
| Japan<ref name="hon">Honshu only</ref> || data-sort-value="I07"|Island 7th largest || 0.228 || 0.15% || 0.10% || -0.05%
|-
| Mainland Britain || data-sort-value="I09"|Island 9th largest || 0.209 || 0.14% || 0.10% || -0.04%
|-
| Island of Ireland || data-sort-value="I20"|Island 20th largest || 0.082 || 0.05% || 0.03% || -0.02%
|}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
Bad map projection #248: Madagascator

Mercator projection but with the North Pole in the Indian Ocean so it exaggerates the size of Madagascar instead of Greenland

{{comic discussion}}

[[Category:Bad Map Projections]]

Talk:2606: Weird Unicode Math Symbols

2022-04-19T04:02:13Z

172.70.110.121: Unhelpful contribution

Apparently, nobody knows what U+237C ⍼ means (https://ionathan.ch/2022/04/09/angzarr.html)
: For me it looks very like as designation of where electrical cable is burrowed. It should come with numbers near angle hands designating depth and offset from sign. But it just a guess, of course [[Special:Contributions/141.101.76.221|141.101.76.221]] 05:30, 14 April 2022 (UTC)

: There are at least four people on (https://news.ycombinator.com/item?id=31012865) who claim to have seen the symbol in the wild: German/Dutch proof by contradiction, diode with a gate, Finnish proofreaders mark indicating when and how to split a word, and indicating which way EM waves are polarized --[[Special:Contributions/162.158.62.180|162.158.62.180]] 11:42, 14 April 2022 (UTC)

: I think that is "larry potter" as the lightning symbol, and the L comes from the L shape the lightning is over imo. [[Special:Contributions/172.70.34.191|172.70.34.191]] 14:47, 14 April 2022 (UTC)Bumpf

Can someone add a column where we try to crowdsource a description for the "mathematical use of symbol" ?

I'm curious what those symbols actually mean, and the unicode titles don't give that much information.

I do not doubt that have enough math geeks on here to find the answer to most of then :-D

Thanks!
[[User:Flekkie|Flekkie]] ([[User talk:Flekkie|talk]]) 01:20, 14 April 2022 (UTC)

i agree w Flekkie's comment
[[User:Blue in real life|Blue in real life]] ([[User talk:Blue in real life|talk]]) 02:27, 14 April 2022 (UTC)

If you make edits, please don't immediately delete all of mine because you think yours are better. It shows you conflicting edits for a reason. Some explanations are nonsensical, like defining a smash product as the "result of dividing two product spaces." The smash product is specifically the quotient of the underlying spaces of two pointed spaces where points in the product spaces are identified if they contain either labeled point as an element. Other claims are simply mistaken. For instance, the ≝ symbol is used to introduce a definition, not to declare that the definition has been achieved in a proof. The claim that "A union on smash product appears to be one where the sets are nit isomorphic" is totally meaningless. The symbol ⩩ is not merely decorative but is intended as a supplemental math symbol like all the others. I couldn't track down its purpose. The APL symbol description somehow never bothers to mention APL. This is all very cursory, which is fine, but just please don't delete my work while doing it. [[Special:Contributions/172.70.130.5|172.70.130.5]] 04:15, 14 April 2022 (UTC)
:I'm done, page is yours. I'd been working on it for an hour and every time I tried to save, a new edit came in. I did my best to reconcile them but by the fifth I just saved a copy of what was there and pasted mine over. I immediately got to work on recovering what I had pasted over as indicated in the edit comment and like I said, I'm done. I've merged to the best of my ability and have no more interest in this page.
:--[[User:FrankHightower|FrankHightower]] ([[User talk:FrankHightower|talk]]) 04:37, 14 April 2022 (UTC)
::I'm very sorry if I was one of those who stepped on your edits. I was originally trying to fix brokenness in the table. ^^^^^ ≫ ^ is the symbol for preferring many small edits over not saving your work often in a batch-mode collaborative editing environment. [[Special:Contributions/172.70.207.8|172.70.207.8]] 04:55, 14 April 2022 (UTC)
:::since adding a column means adding a cell to every row, I thought it would be easier/better to put something in each cell. I wasn't expecting this --[[User:FrankHightower|FrankHightower]] ([[User talk:FrankHightower|talk]]) 18:12, 15 April 2022 (UTC)
:: Don't worry about it, idk why I was so upset. It's that feeling you get when you click "save" and then suddenly it's gone. If anything's still missing, I'll just restore it. [[Special:Contributions/172.70.131.106|172.70.131.106]] 05:41, 14 April 2022 (UTC)

I wish we had as much research on ⧍ and ⩩ as we have for ⍼. [[Special:Contributions/172.70.207.8|172.70.207.8]] 05:16, 14 April 2022 (UTC)
: No clue what those are for. The first is a triangle with serifs? The triangle symbol (not capital delta) is often used in geometry to represent a triangle, but why in the world would you give a geometric figure serifs? I think I may have seen the triple cross-hatch somewhere, but I couldn't say where. Maybe it's the chess commentary symbol for being mated so badly it's embarrassing. [[Special:Contributions/172.70.131.106|172.70.131.106]] 05:41, 14 April 2022 (UTC)
:: I'm guessing what must have happened is the [https://decodeunicode.org/en/u+2A00 code page in question] was filled in by a typographer with more graphic design than mathematical experience, who likely added made-up "missing" symbols as the design-logical extensions of the symbols they were given, presumably to be on the safe side in case they had what appeared to be a possibly incomplete set. There are some awesome ones in there, like "⩐" TEST-TUBE PARTHENOGENISIS, and "⨻" THE ILLUMINATI IS DEAD. [[Special:Contributions/162.158.255.171|162.158.255.171]] 06:07, 14 April 2022 (UTC)
: The ⧍ character has the same origin as ⍼, namely that they were both part of ISO/IEC TR 9573-13 with no explanation given. You can find it in some old charts online, like here: [https://www.w3.org/TR/REC-MathML/chap6/ISOAMSBe2.html], under `trisb`/codepoint E27E. [[User:Ionchy|ionchy]] ([[User talk:Ionchy|talk]]) 07:03, 14 April 2022 (UTC)
:: I am sure that I have seen maps with such a symbol used for campsites, and without the bold strokes of the top sides as the National Park Service draws it. I haven't found any yet, but I have found one without the center base -- like _/\_ -- on a 1960s era map. [[Special:Contributions/172.69.134.131|172.69.134.131]] 07:07, 14 April 2022 (UTC)
: As for ⩩, the character just before it in the Unicode code chart [https://www.unicode.org/charts/PDF/U2A00.pdf], ⩨, has the text "identical and parallel to", so it's possible the horizontal lines in this one also means "identical to". I don't know what three vertical lines mean though, and in Unicode there's three (!) different characters with similar glyphs: U+2980 ⦀, U+2AF4 ⫴, and U+2AFC ⫼. [[User:Ionchy|ionchy]] ([[User talk:Ionchy|talk]]) 07:28, 14 April 2022 (UTC)
:: Identical both vertically and horizontally? [[Special:Contributions/172.69.134.131|172.69.134.131]] 07:32, 14 April 2022 (UTC)
:: I found one suggestion that the dodecathorp should be used to refer to very big numbers...[[Special:Contributions/172.69.79.223|172.69.79.223]] 08:33, 14 April 2022 (UTC)
:: Three vertical bars means "similar to", so that'd be identical to and similar... to. OK that doesn't work.
[[Special:Contributions/172.70.110.121|172.70.110.121]] 04:02, 19 April 2022 (UTC)

Apparently, Randall reads Hacker News like the rest of us... --[[Special:Contributions/172.68.110.141|172.68.110.141]] 09:38, 14 April 2022 (UTC)

Did you know that ⩩ was a logo of the Romanian fascist group Iron Guard?[[Special:Contributions/172.68.238.67|172.68.238.67]]
:Wow. "Saint Michael's Cross, the ({{w|Iron Guard}}) movement's symbol designed by Codreanu." I prefer the 4x4 tic-tac-toe board.... [[Special:Contributions/172.69.33.181|172.69.33.181]] 12:29, 14 April 2022 (UTC)

Not that I have special knowledge (above aspiring-polymath level), but for "Rightwards Arrow Above Reverse Almost Equal To" and its leftwards sibling (the current suggestion being that it's an assignment of an approximation) I'd posit that it's a directional approximation specific to chaotic systems. For a precise a=b in a system where small changes to one side can effect large changes in the other, uncertainty or deliberate approximation of either of them ''may'' still map well enough to the value across the desired ≈ relationship, but that is only acceptably so unidirectionally. Hence (and I wouldn't know which would be the better convention) the arrow depicts the direction of either the dependence or the more dominant option, whichever it is that almost-ties the values tovether. (I also really ought to check what the ''reverse'' almost-equal-to sign is used for, it could be radically different from the 'forwards' version in some field, for which the directionality might even be trivially understood by context.) [[Special:Contributions/172.70.91.36|172.70.91.36]] 11:25, 14 April 2022 (UTC)
:Any sources? I found several papers on the topic you describe naively searching on those keywords, and while they are packed with notation, I couldn't find any arrows or approximate equality signs, let alone any sort of composition of the two. [[Special:Contributions/172.69.33.51|172.69.33.51]] 12:47, 14 April 2022 (UTC)
::No sources except in my (above-IP's, just to confirm) head. It's just something I ''might'' use it for, if let loose on a whiteboard for some reason, not something for which I've seen it used. It's a situation I've encountered often enough in my own amateur numerical analysis, but under self-taught/self-experimenting circumstances where I was probably just (inefficiently) re-inventing the wheel. And if I've been commenting code (itself strings of conventional syntactical symbols), as a usually futile attempt to remind future-me what I was doing, I would have been using longhand to describe what I was either basing my functions on or actually asking them to test... So no surprise that a paper-search didn't match much of my description. ;) [[Special:Contributions/172.70.162.155|172.70.162.155]] 14:39, 14 April 2022 (UTC)

No idea how Randall got that wrong, but U+2A50 (⩐) is totally catching a snowflake with your tongue. [[Special:Contributions/172.68.110.141|172.68.110.141]] 15:02, 14 April 2022 (UTC)

While cute, I think it'd probably be better to remove the Unicode letters in the chart for the second hashtag (⩩). Not only would it mess up screenreaders, but it doesn't actually look like the image in question. Perhaps it would be better to upload an image and give it some alt text to describe it.
--[[User:Trlkly|Trlkly]] ([[User talk:Trlkly|talk]]) 00:12, 15 April 2022 (UTC)
:Could the strange-looking characters be made to look like the image in question using Unicode combining diacritical marks? [[User:BunsenH|BunsenH]] ([[User talk:BunsenH|talk]]) 15:31, 15 April 2022 (UTC)
:A screen reader should read it as "Double struck H, Double struck a, double struck s..." etc. which seems a pretty accurate readout to me --18:12, 15 April 2022 (UTC)

== Calming down - Sigma long S ==

Calming down may refer to the pronounciation of the Letter Esh https://en.m.wikipedia.org
/wiki/Esh_(letter)

"Other links: XKCD #2606 mentions ⍼ and its Explain XKCD entry cites this post" yooo people the blog post now mentions us! Someone put this in trivia or something [[User:Mushrooms|Mushrooms]] ([[User talk:Mushrooms|talk]]) 09:01, 15 April 2022 (UTC)
:Ah, yes, so the article we reference that we think Randall references has now referenced both him and us and so now we ought to reference that? [[978: Citogenesis|Seems perfectly Ok to me!]] :-p
:(P.S. Hello to that author. You should just be glad that you're not Wikipedia... ;) ) [[Special:Contributions/172.70.162.147|172.70.162.147]] 11:19, 15 April 2022 (UTC)
::The blog author is [[User:Ionchy]], who has contributed to the discussion above. [[Special:Contributions/172.70.211.72|172.70.211.72]] 13:47, 15 April 2022 (UTC)

Any of these that are particularly obscure and someone doesn't find and post here what its actual existing use is will be impossible to research later, as people talking about this comic will end up dominating the results of any attempt to search for the symbol.--[[Special:Contributions/108.162.216.27|108.162.216.27]] 00:08, 19 April 2022 (UTC)

Talk:2607: Geiger Counter

2022-04-16T06:32:17Z

172.70.110.121:

Vanilla joke, but funny. [[User:Nafedalbi|Nafedalbi]] ([[User talk:Nafedalbi|talk]]) 18:41, 15 April 2022 (UTC)Nafedalbi
:It's Randall's "dad joke". [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 19:23, 15 April 2022 (UTC)
:Honestly, yeah. I impulsively went "wow... Randall's really jumped the stick figure shark." --[[Special:Contributions/172.70.110.121|172.70.110.121]] 06:32, 16 April 2022 (UTC)

I added telegraph wires (UK-only term, possibly, and anachronistic as they are telephone cables, so feel free to change to be US-centric) and birds seem happy to sit on pole-suspended POTS cables as much as power-lines, so the linked heat-effect thing is definitely a minority necessity. I think it's just a perch. Though we probably have more signal-wires. Most(?) streets more than a few decades old have telegraph poles feeding wires to established properties (even if cable/FTTP has been dug into trenches) but mains electricity tends to have been subsurface for much longer, with only HV national/rural-area transmission grids up on pylons/poles. Obviously there ''are'' a lot more perching birds out in the countryside, where they may dominate (but still the 'telegraph' may follow road or rail routes to service the villages and isolated inhabitations along them) but you don't tend to see birds atop the larger lines at all... Too high up? ''Too'' hot? I've seen rooks/etc happily doing a Hitchcock upon a pylon itself, apparently enjoying the communal view. [[Special:Contributions/172.70.90.63|172.70.90.63]] 18:54, 15 April 2022 (UTC)

For the record, [[User:Avni]] at 19:30 UTC on 2022-04-15 [https://www.explainxkcd.com/wiki/index.php?title=2607:_Geiger_Counter&diff=next&oldid=230502 deleted everything on this page] 
--[[User:FrankHightower|FrankHightower]] ([[User talk:FrankHightower|talk]]) 04:11, 16 April 2022 (UTC)

The title text joke may be understood more easily by reading "stood under" in place of "understood". [[Special:Contributions/162.158.107.124|162.158.107.124]] 19:37, 15 April 2022 (UTC)

Living in Manhattan, you learn to notice when an area is full of bird droppings and avoid standing there. You also need to pay attention when parking your car. Certain lamp posts (where the lamp is cantilevered over the street) near Central Park often tend to have a large accumulation under them. [[Special:Contributions/108.162.246.178|108.162.246.178]] 19:47, 15 April 2022 (UTC)

I do not understand the joke in the title text, so if somebody could please write an explanation, that would be great.
Also, this is my first ever full comic description! Yay!
I don't know what categories this fits in, if somebody could also put those in that would be great. [[User:MrYellow04|MrYellow04]] ([[User talk:MrYellow04|talk]]) 19:58, 15 April 2022 (UTC)
:I suggest you stand under a wire with lots of birds on it for a while. It will hit you. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 20:32, 15 April 2022 (UTC)

Randall, come here. Yes, right there. Stand still. THWACK! THWACK THWACK THWACK THWACK THWACK! That is all, you may go now. 20:41, 15 April 2022 (UTC)

The explanation makes clear the side of the pun regarding the Geiger counting clicking, but for non-native English speakers, the phrase "it clicked" meaning "I understood" may need clarification. [[Special:Contributions/162.158.166.213|162.158.166.213]] 21:17, 15 April 2022 (UTC)

I thought it meant the birds were dangerously mutated because of the radioactivity, but now I understand. [[Special:Contributions/172.69.34.84|172.69.34.84]] 22:00, 15 April 2022 (UTC)
:Just make sure you don't open your mouth and tilt your head back. [[Special:Contributions/172.70.90.63|172.70.90.63]] 22:59, 15 April 2022 (UTC)

Also possibly related to this news story https://www.reuters.com/world/europe/unprotected-russian-soldiers-disturbed-radioactive-dust-chernobyls-red-forest-2022-03-28/

2605: Taylor Series

2022-04-13T00:31:43Z

172.70.110.121:

{{comic
| number = 2605
| date = April 11, 2022
| title = Taylor Series
| image = taylor_series.png
| titletext = The Taylor series should have been canceled after the first term.
}}

==Explanation==
{{incomplete|Created by THE MACLAURIN SERIES EVALUATED AT X PLUS EPSILON - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

In mathematics, the {{w|Taylor series}} of a function is an infinite sum of terms that are expressed as the function's {{w|Derivative|derivatives}} multiplied with a coefficient, giving a polynomial approximation of the function at a specific point. Their expressions, usually referred to as "expansions," continue (except for - possibly piecewise - polynomial functions - for those the Taylor series would finally result in the originating polynomial function) without end. Taylor series are useful for approximating smooth functions within the neighborhood of a point. They are also useful for deriving numerical approximations of {{w|Irrational number|irrational}} values, {{w|Machin-like formula|such as π}}, as well as {{w|Symbolic integration|symbolic}} forms to make them easier to integrate or otherwise manipulate with calculus.[https://www.mathsisfun.com/algebra/taylor-series.html] However, because they involve difficult calculus operations, and can be annoyingly tedious to {{w|Numerical analysis|calculate by hand}}, they are often not loved by math students{{citation needed}}.

[[Miss Lenhart]] appears to be teaching a class about how to use a Taylor series. She has explained what one is, and how it is used. She presumes her students want to keep learning about the series, in that they, "wish it would never end." She then says "Good news!" because the Taylor series does not end, each term being smaller than the last (in the vicinity of the point) as the exponent of the distance increases by one. The cartoon's humor is based on contrasting the idea of wishing the series will never end, which is ordinarily expressed regarding long-running sequences of enjoyable events, with the infinite nature of the Taylor series, which is probably not appreciated by her students struggling to understand why the sums {{w|Convergent series|converge}} to their resulting value.

The title text is a reference to the common practice among physicists and engineers of abbreviating the Taylor series to only the first few terms, typically one or two, in order to simplify the mathematics of their models. The title text is also a pun on the use of the word "series" to refer to a television program. It symbolizes the terms of the mathematical series as a {{w|metaphor}} with a television season, suggesting that only the first term is useful. It makes fun of the common sentiment against bad {{w|screenwriting}} of a series by saying that, "The series should have been cancelled after the first season," replacing "season" with "term." It should be noted that there do indeed exist functions for which the Taylor series has effectively only one term -- specifically, functions with a degree of zero, or where y is a constant value. All of the derivatives of these functions are zero, and thus the Taylor series is effectively a single term -- just the value itself.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Miss Lenhart pointing a stick at a whiteboard, which has some scribbled text written on it and one line is circled.]
:Miss Lenhart: At this point, you're probably thinking, "I love this equation and wish it would never end!"
:Miss Lenhart: Well, good news!

:[Caption below the panel:]
:Taylor series expansion is the worst.

{{comic discussion}}

[[Category:Comics featuring Miss Lenhart]]
[[Category:Math]]

1589: Frankenstein

2022-04-08T22:36:39Z

172.70.110.121: Typo

{{comic
| number = 1589
| date = October 12, 2015
| title = Frankenstein
| image = frankenstein.png
| titletext = "Wait, so in this version is Frankenstein also the doctor's name?" "No, he's just 'The Doctor'."
}}

==Explanation==
''{{w|Frankenstein|Frankenstein; or, The Modern Prometheus}}'' is a novel by Mary Shelley published in 1818. In it, Victor Frankenstein is a human who creates a {{w|Frankenstein%27s_monster#Namelessness|monster}} (who is never named). In popular culture, however, "Frankenstein" is taken to be the name of the monster, not its creator.

While this is an often-corrected "error", it has been argued that it is not technically incorrect to call the monster "Frankenstein" as well, since he is the "offspring" of his "father", Victor Frankenstein. Since a child usually takes on the last name of their father, it may be said that the monster's last name actually ''is'' "Frankenstein". He also refers to himself in the novel as "the Adam of your labors" - a reference to the Biblical Adam, the first of his kind - and some have taken to calling the monster "Adam Frankenstein" to differentiate him from the scientist, Victor Frankenstein.

Others have argued that the monster's namelessness is an important part of his characterization in the story since it reflects the doctor's complete rejection of his creation. While the monster identifies Victor as his "father" in the novel, Victor does not consider the creature to be his "son".

[[Randall]] apparently finds this argument tedious and pedantic, so he has created his own work of fiction, in which the monster is named Frankenstein. He rationalizes that it is now correct to call the monster Frankenstein, assuming that his comic strip is as authoritative as the original novel. "{{w|Canon (fiction)|Canonical}}" (rule, standard) means that this comic should be used as the authoritative work on the naming of the monster.

However, xkcd's ''Frankenstein'' would be unlikely to be accepted by anyone as canonical, except for its stated purpose of settling the naming argument. The original version of any story is usually assumed to be the canonical one, and any derivative work would have to have widespread influence and recognition to supplant it in the popular imagination. This is not likely to happen with xkcd's ''Frankenstein,'' as it makes almost no effort to stand on its own; it exists only to be a version of ''Frankenstein'' where the monster is named "Frankenstein." It emphasizes this point several times, and ends within a single panel, having accomplished its only goal. Almost no readers would find this version entertaining or substantive enough to displace Mary Shelley's original as the definitive version of the story.

The {{w|Public_domain|copyright}} on Mary Shelley's novel has expired long ago, so it is perfectly legal to create works derived from the original story. It should be noted, however, that Universal holds the copyright on the common [https://www.plagiarismtoday.com/2011/10/24/how-universal-re-copyrighted-frankensteins-monster/ image of the monster] (green skin, flat-top head, scar, bolts on the neck and protruding forehead). To qualify as a {{w|derivative work}} the story needs to be substantially different from the original. The monster believing in {{w|moon landing conspiracy theories}} would probably qualify, but may reference retellings of the tale where a damaged or deranged brain was used (as an alternate 'explanation' why the supposedly perfect creation inevitably runs amok). Additionally, the original Frankenstein's monster was seen by its creator as hideous and repulsive due to its physical appearance despite the project being a success. Randall makes the same correlation in his version by having Frankenstein claim the moon landings were faked, which produces the same feelings in The Doctor.

Alternatively, the monster being a moon landing denier is meant as a throwaway absurdist non sequitur. As the only point of this story is to make a canonical version of ''Frankenstein'' where "Frankenstein" is the monster's name, it should logically end once it has finished making that point clear. However, Randall throws a curveball by having the monster blurt out an uncomfortable and controversial point of view before the ending, then ending the story abruptly before the monster's statements can be addressed.

It is also possible that Randall is making reference to the fact that the kind of people who become engrossed in the debate that is attempted to be resolved in this comic and would bother to create a piece like this (which incidentally, complicates matters further rather than simplifying it, similar to the effect of many pieces of evidence in internet discussions) could be compared to the kind of people who deny the Moon Landings in obscure forums. He is drawing attention to how inane and unnecessary the comic is.

The title text raises the question of what the monster's creator is named in this version, since the name "Frankenstein" is instead given to the monster. The canonical answer is that the creator is simply "The Doctor", like the title character of the series {{w|Doctor_Who|"Doctor Who"}}. This might be a reference to similar pedantic nitpicking that occurs when that character is incorrectly referred to as "Doctor Who" rather than "The Doctor" which is in turn referenced in comic [[1221: Nomenclature]]. As it happens, people who make that mistake can also claim canonical support, in that some early episodes of the series list the character's name as "Doctor Who" in the credits, or reference the recharacterisation in the {{w|Dr. Who (Dalek films)|cinematic retellings}}.

==Transcript==
:[A text only panel. Between the last two lines is a lightning bolt.]
:Like many people, I'm tired of the nitpicking about Frankenstein's monster's name.
:Luckily, ''Frankenstein'' is public domain.
:Therefore, I present
:xkcd's
:'''''Frankenstein'''''
:(''The monster's name'')

:[Cueball is turning down a lever while looking at a monster with black hair that is lying on a bed under a bedsheet. There are two wires connecting to the neck of the monster.]
:Frankenstein: ''Graaar''!
:Cueball: Frankenstein is alive! I am a modern Prometheus!
:Frankenstein: ''Raaaar''!
:Cueball: To be clear, your name is ''Frankenstein'', canonically.
:Frankenstein: ''Graaaaar''!
:Frankenstein: ''The moon landings were faked''!
:Cueball: Wait, what?

:[Another text only panel. The first word is written between two curvy lines.]
:'''Fin.'''
:There.
:Feel free to call the monster "Frankenstein."
:If anyone tries to correct you, just explain that this comic is your canonical version.
:Thank you.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Fiction]]
[[Category:Doctor Who]]

2231: The Time Before and After Land

2022-04-08T04:50:33Z

172.70.110.121:

{{comic
| number = 2231
| date = November 20, 2019
| title = The Time Before And After Land
| image = the_time_before_and_after_land.png
| titletext = According to Google, "the time for Beeland" is apparently whenever you're looking for delicious honey in Spillimacheen, British Columbia or a hexagonal chalet in the Savinja valley in Slovenia.
}}

==Explanation==
This comic indulges in some wordplay on the title of the 1988 animated movie ''{{w|The Land Before Time (franchise)|The Land Before Time}}'', which takes place millions of years ago in the time of dinosaurs.

The comic shows a timeline of the history of the universe from the {{w|Big Bang}} to the present day, with ''The Land Before Time'' placed at the point in the timeline where the movie is set, as well as other seemingly arbitrary events such as the formation of rocky planets and the evolution of ground-nesting bees. The joke is that Randall has contrived several periods of universal history that sound like funny permutations of "The Land Before Time" due to certain words being {{w|homophone}}s, such as "time" and "thyme", or homonyms, such as the noun "land" (ground) and the verb "land" (to alight). He also split the word "before" into "bee" and "for".

The title text is for the phrase "the time for Beeland" and lists 2 places (that Randall found on Google) with the name "Beeland": [http://beeland.ca/ a market in Spillimacheen, British Columbia] or [http://www.apartmajimozirje.si/en/beeland/ a chalet in Slovenia].

Bees are a [[:Category:Bees|recurring topic]] on xkcd.

===Explanation of time ranges on the chart===

{| class="wikitable"
! Range !! From !! To !! Explanation
|-
|width=15%|'''The time before land'''
|width=10%|Big Bang
|width=10%|Rocky planets form
|width=65%|The {{w|Big Bang}} is a scientific theory that attempts to describe the very earliest conditions in our universe, but is also used informally as a synonym for the beginning of the universe. The early universe contained only simple elements such as hydrogen, but over time, star formation led to the creation of new, heavier elements, which eventually gave rise to planets with a rocky surface, which we call "land". It would have taken billions of years for the first such land-bearing planet to appear in the universe, so this time period could be considered "the time before land".
|-
|'''The time before bees'''
|Big Bang
|Ground-nesting bees evolve
|This time range also includes the formation of the Earth, a necessary precondition for bees to evolve. Any time before the evolution of bees could be considered "The time before bees". While the chart does not account for the possibility that non-ground-nesting bees may have existed prior to ground-nesting ones, evidence strongly suggests that the common ancestor to all bees nested in the ground rather than forming hives.
|-
|'''The land before thyme'''
|Rocky planets form
|''Thymus'' genus diverges
|''Thymus'' is the genus of plant that is called "{{w|thyme}}" in English, and it is pronounced exactly the same way as "time". By "diverges", it is meant that this is the point in time at which the ''Thymus'' genus of plants split off from their ancestral line - ie. when thyme first evolved. This time range is after land first appears in the universe, but before {{w|thyme}} evolved - therefore, any land that existed within this time range can be considered "the land before thyme". When said, this sounds exactly the same as "''The Land Before Time''".
|-
|'''Time for land bees!'''
|Ground-nesting bees evolve
|Now
|When conditions change to allow an event to occur, people sometimes say "time for (event)!". In this case, the event is the emergence of ground-nesting bees, which could be considered "land bees".
|-
|'''Bees land on thyme'''
|''Thymus'' genus diverges
|Now
|Bees are flying insects, and therefore must land in order to rest before taking off again. Now that thyme has evolved, bees are able to land on thyme plants. This is a play on two different meanings of the word "land"; as a noun, it means solid ground, but here, it is a verb which means to alight or stop flying.
|}

==Transcript==
:[Caption at top of panel:]
:(Timeline not to scale)

:[A timeline is shown with two endpoints and five other points. The points are labeled:]
:Big Bang
:Rocky planets form
:Earth forms
:Ground-nesting bees evolve
:''The Land Before Time''
:''Thymus'' genus diverges
:Now

:[Below the timeline are five overlapping time periods in three rows. The text is between two thick black bars. The time periods all start and end at two different points.]

:[Big Bang to Rocky Planets Form:]
:The Time Before Land

:[Big Bang to Ground-Nesting Bees Evolve:]
:The Time Before bees

:[Rocky Planets Form to ''Thymus'' Genus Diverges:]
:The Land Before Thyme

:[Ground-Nesting Bees evolve to Now:]
:Time for Land Bees!

:[Thymus Genus Diverges to Now:]
:Bees Land on Thyme

{{comic discussion}}

[[Category:Timelines]]
[[Category:Fiction]]
[[Category:Bees]]
[[Category:Time]]
[[Category:Puns]]

2595: Advanced Techniques

2022-03-21T15:14:38Z

172.70.110.121: grammar fixes

{{comic
| number = 2595
| date = March 18, 2022
| title = Advanced Techniques
| image = advanced_techniques.png
| titletext = A blow from Emmy's Cutlass of Variations will transport the dragon to a corresponding symmetric position in the Noetherworld.
}}

==Explanation==
{{incomplete|Created by AN EULISH CLAUSS- Please slay the CORRECT dragon when editing this page. Do NOT travel to the Noetherworld. Do NOT pass Go. Please collect the correct sedenion.}}
In typical [[Miss Lenhart]] fashion, she is teaching a mathematics class where she outlines a process by which a mathematical result is achieved through steps which sound suspiciously like magical "{{w|Role-playing game}} (RPG) logic." She both includes dragons and arrows to slay it.

One of her students asks if this is a metaphor for the technique, but her rather tetchy reply ''Does this look like English class?!''' seems to imply that she literally means that dragons and arrows will be employed in the resolution of the problem. It is also clear from the slide she is pointing at that she has drawn a dragon and a man with a bow that is aiming an arrow at the dragon.

The caption beneath the comic states that this approach describes "All advanced math techniques." This is probably a reference to {{w|Arthur C. Clarke}}'s {{W|Clarke's three laws|third law}} that ''Any sufficiently advanced technology is indistinguishable from magic'', but re-framed for mathematics. What [[Randall]] is implying is that all advanced math techniques looks like magic to normal people.

Whilst metaphor is an important part of many languages, and so definitely taught in for instance English and French classes, it is not usually used in math classes. The process of algebra denoting variables with letters could though be considered related to metaphorical thinking.

Invocations are a common classification for spoken or vocalized types of spell. In the logic Miss Lenhart used, 'invoking' Gauss's operator may refer to casting a magical spell with verbal components (such as [https://roll20.net/compendium/dnd5e/True%20Polymorph True Polymorph]). The operator is named after the famous German mathematician {{w|Carl Friedrich Gauss}}. There is nothing on Wikipedia called Gauss's operator, but there is both {{w|Gauss's law}} and the {{w|Gauss–Kuzmin–Wirsing operator}}. As neither can transform an equation into a dragon, it is not certain what, if anything real, Miss Lenhart references.

Slaying the dragon with Hilbert's arrow indicates that the arrow has some magical properties. The arrow could be named after {{w|David Hilbert}}, for instance, known for {{w|Hilbert space}}. Hilbert space converts subsets of an infinite vector space into a complete metric space, allowing the use of linear algebra & calculus methods which might otherwise be applicable only to finite Euclidean spaces. Vectors could be compared with an arrow.

Magical arrows are frequently used to slay dragons, in myth and role-playing games. Magical items in RPGs such as {{w|Dungeons & Dragons}}, are often named after a creator or famous user; hence, a magical "Arrow of Hilbert," might traverse infinite spaces or affect targets for which one or more stats are effectively infinite.

{{w|Conway chained arrow notation}} (2→3→4) is a means of expressing extremely large numbers and one of many uses for arrows in mathematics.

There is in fact a class of {{w|Dragon curve}}s, which do have the sort of S-shape shown on the whiteboard, but they have no connection to Gauss's operator, and are not actual dragons that need slaying.

Basically Miss Lenhart will turn the unsolvable equation into a dragon using Gauss's operator, then kill it with Hilbert's arrow. The now dead dragons corpse will then be transformed into the solution of the original equation, QED.

Miss Lenhart could be describing techniques like {{w|Fourier analysis}}, in which a problem is transformed from one domain into another which is more tractable (e.g. from the time domain to the frequency domain, commonly done for analyzing the behavior of signals or dynamical systems) and then back again.

The title text contains two puns and a reference. The phrase "{{w|Cutlass}} of Variations" is a pun on the mathematical technique called "{{w|Calculus of variations}}". The word "Noetherworld" is a pun on "{{w|underworld|netherworld}}". The reference is to the mathematician {{w|Emmy Noether}}, who was a giant in the field of abstract algebra. Furthermore, so-called {{w|Noether's Theorem}} is used in the Calculus of Variations. She was previously referenced as one of many important women in science back in [[896: Marie Curie]].

==Transcript==
:[Miss Lenhart is using a stick to point at a whiteboard behind her while facing, presumably, a crowd of off-panel students. The white board has a drawing of a snake-shaped dragon with wings, flying with it's body in an S-shape. An archer is pointing an arrow up at the dragon above him. Above the drawings there are three and below two rows of unreadable text and equations.]
:Miss Lenhart: To solve this equation, we invoke Gauss's operator to transform it into a dragon.
:Miss Lenhart: Then we slay the dragon with Hilbert's Arrow, and transform its corpse back into the solution.
:Off-panel voice: Just to be clear, this is a metaphor, right?
:Miss Lenhart: Does this '''''look''''' like English class?!

:[Caption below the panel:]
:All advanced math techniques

{{comic discussion}}

[[Category:Comics featuring Miss Lenhart]]
[[Category:Math]]

2593: Deviled Eggs

2022-03-15T03:14:04Z

172.70.110.121: Wikipedia links

{{comic
| number = 2593
| date = March 14, 2022
| title = Deviled Eggs
| image = deviled_eggs.png
| titletext = The foil on the toothpick represents the blue flash.
}}

==Explanation==
{{incomplete|Created by a HEN - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

A [https://en.wikipedia.org/wiki/Deviled_egg deviled egg] is a dish created by cutting a hard-boiled egg into halves and replacing the yolk with a paste frequently made from the yolk itself. Randall Monroe parodies the dish by creating several alternative versions of the dish for other professions using word plays on the name of the dish.

Many landscaping projects require a leveled ground to work on{{Citation needed}}. As such, a landscaper may prefer serve their deviled egg with a perfectly flat surface.

Bevel is a design pattern of creating non-perpendicular surfaces between adjacent edges. A designer may prefer to serve their eggs with beveled edges to give their eggs a more modern, aesthetically pleasing look.

The {{w|Demon core}} is a piece of sub-critical plutonium created during the Manhattan Project to investigate the properties of criticality. The piece of plutonium got its name from the 2 criticality incidents that occurred when scientists were investigating this property. The first accident resulted in the death of {{w|Harry Daghlian}}. In the second experiment, the core was covered between two neutron reflecting shells separated by a screwdriver. The screwdriver became dislodged, causing the core to become completely covered by the neutron reflecting shell, bringing the core past its criticality limit. A large amount of radiation caused the subsequent death of physicist {{w|Louis Slotin}}. The dome of the boiled egg and the toothpick resemble the configuration of the experiment.

The title texts revers to the [https://en.wikipedia.org/wiki/Cherenkov_radiation Cherenkov Radiation], the "sonic boom" created by particles travelling faster than the speed of light in a medium.

==Transcript==
(Below image of ordinary deviled egg) '''Chef''' Deviled Egg (Below image of flat deviled egg resembling half of a hard-boiled egg) '''Landscaper''' Leveled Egg (Below image of egg resembling ordinary deviled egg, except with edges of white chamfered) '''Designer''' Beveled Egg (Below image of egg with hemispherical white as before, but full spherical yolk within and feathered toothpick inserted into core yolk sideways at a slight angle to the equator) '''Physicist''' Demon Egg{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}
This comic is one of a limited number containing color; in this case, the yellow of the egg yolk, burnt red of presumably paprika, and blue toothpick foil are the only colors added. The toothpick foil is drawn in a way vaguely resembling arrow feathering.

2593: Deviled Eggs

2022-03-15T03:12:48Z

172.70.110.121: Clarifying experiments

{{comic
| number = 2593
| date = March 14, 2022
| title = Deviled Eggs
| image = deviled_eggs.png
| titletext = The foil on the toothpick represents the blue flash.
}}

==Explanation==
{{incomplete|Created by a HEN - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

A [https://en.wikipedia.org/wiki/Deviled_egg deviled egg] is a dish created by cutting a hard-boiled egg into halves and replacing the yolk with a paste frequently made from the yolk itself. Randall Monroe parodies the dish by creating several alternative versions of the dish for other professions using word plays on the name of the dish.

Many landscaping projects require a leveled ground to work on{{Citation needed}}. As such, a landscaper may prefer serve their deviled egg with a perfectly flat surface.

Bevel is a design pattern of creating non-perpendicular surfaces between adjacent edges. A designer may prefer to serve their eggs with beveled edges to give their eggs a more modern, aesthetically pleasing look.

[https://en.wikipedia.org/wiki/Demon_core The Demon Core] is a piece of sub-critical plutonium created during the Manhattan Project to investigate the properties of criticality. The piece of plutonium got its name from the 2 criticality incidents that occurred when scientists were investigating this property. The first accident resulted in the death of {w|Harry Daghlian}. In the second experiment, the core was covered between two neutron reflecting shells separated by a screwdriver. The screwdriver became dislodged, causing the core to become completely covered by the neutron reflecting shell, bringing the core past its criticality limit. A large amount of radiation caused the subsequent death of physicist [https://en.wikipedia.org/wiki/Louis_Slotin Louis Slotin]. The dome of the boiled egg and the toothpick resemble the configuration of the experiment.

The title texts revers to the [https://en.wikipedia.org/wiki/Cherenkov_radiation Cherenkov Radiation], the "sonic boom" created by particles travelling faster than the speed of light in a medium.

==Transcript==
(Below image of ordinary deviled egg) '''Chef''' Deviled Egg (Below image of flat deviled egg resembling half of a hard-boiled egg) '''Landscaper''' Leveled Egg (Below image of egg resembling ordinary deviled egg, except with edges of white chamfered) '''Designer''' Beveled Egg (Below image of egg with hemispherical white as before, but full spherical yolk within and feathered toothpick inserted into core yolk sideways at a slight angle to the equator) '''Physicist''' Demon Egg{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}
This comic is one of a limited number containing color; in this case, the yellow of the egg yolk, burnt red of presumably paprika, and blue toothpick foil are the only colors added. The toothpick foil is drawn in a way vaguely resembling arrow feathering.

2589: Outlet Denier

2022-03-05T07:59:16Z

172.70.110.121: