explain xkcd - User contributions [en]

Talk:981: Porn Folder

2021-07-22T20:12:56Z

172.70.98.96:

Its not difficult to do that. {{unsigned ip|200.196.51.166}}

What?
Apply subjective motivations to subjects?

It may easy but you would soon learn not to.[[User:Weatherlawyer| I used Google News BEFORE it was clickbait]] ([[User talk:Weatherlawyer|talk]]) 12:19, 22 January 2015 (UTC)

Xcopy would be a killer. [[User:Jakee308|Jakee308]] ([[User talk:Jakee308|talk]]) 10:59, 16 June 2015 (UTC)

----

I did this. Way, way back, in version 7 (I said way, way back), the convention of directory entries "." and ".." was only a convention, not enforced. It was possible, and I did, make a directory where ".." did NOT go to the parent directory, but went to a hidden directory. Only I could find the files there.

This ended when system 3's fsck found that directory, and put it in lost+found.

--[[User:Keybounce|Keybounce]] ([[User talk:Keybounce|talk]]) 07:38, 4 August 2017 (UTC)

You can just make an alias of a file and copy that into itself.

I think this explanation misses the fact that the comic plays on the meaning of the phrase "porn folder," where the usual usage suggests it is the "folder where porn is kept" but the comedic usage is, "the folder itself is porn."

2492: Commonly Mispronounced Equations

2021-07-22T17:12:23Z

172.70.98.96: /* Explanation */ title text

{{comic
| number = 2492
| date = July 21, 2021
| title = Commonly Mispronounced Equations
| image = commonly_mispronounced_equations.png
| titletext = "Epsihootamoo doopsiquorps" --the Schrödinger equation for the hydrogen atom
}}

==Explanation==
{{incomplete|Created by a LAGRONJ EYSIBARYMOODMOOSIOYLERSIBRYMOOAMOOBAMOOSIMASIBRSIQORTFAHMOOVYFAHMOOVY. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

This comic is a collection of famous physical and mathematical equations, along with their "correct" pronunciations. Equations are normally voiced out loud either by their names ("Mass–energy equivalence") or by saying the parts out loud using normal linguistic rules ("E equals M C squared"). This comic instead asserts that equations are meant to be said out loud like words, using their own set of phonic rules.
Though this premise may seem absurd, sometimes this kind of pronunciation is used as an abbreviation or a mnemonic device. For example, the equation A=Pert used for compound interest is commonly taught and pronounced as the "pert" equation, while SOH-CAH-TOA is used as a mnemonic for the equations for sine, cosine, and tangent (Sine: Opposite over Hypotenuse, etc.).

List of equations:
* {{w|Newton%27s_law_of_universal_gravitation|Newton's law of universal gravitation}}
* {{w|Mass%E2%80%93energy_equivalence|Mass-energy equivalence}}
* {{w|Pythagorean_theorem|Pythagorean theorem}}
* {{w|Area_of_a_circle|Area of a circle}}
* {{w|Entropy_(information_theory)|Shannon entropy}} and {{w|Diversity_index#Shannon_index|Shannon index}}
* {{w|Ideal_gas_law|Ideal gas law}}
* {{w|Euler%27s_identity|Euler's identity}}
* {{w|Newton's_laws_of_motion#Newton's_second_law|Newton's 2nd law of motion}}
* {{w|Wave_equation|Wave equation}} (c should be c2)
* {{w|Derivative#Definition|General derivative}}
* {{w|Quadratic formula}}
* (title text) {{w|Schrödinger_equation|Schrödinger equation}}

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

[Four rows of equations, the top three rows each containing three equations and the bottom row containing two equations. Each equation is enclosed in a rectangular box and has a suggested phonetic pronunciation below it.]

F = G * (m1 * m2)/r^2 
FUH-'''JAM'''-ER

E = m * c^2 
'''EM'''-CAH-TOO

a^2 + b^2 = c^2 
AT-'''BOOT'''-COOT

{{comic discussion}}
[[Category:Physics]]
[[Category:Math]]
[[Category: Language]]

2491: Immune Factory

2021-07-20T16:51:18Z

172.70.98.96: /* Transcript */ pun

{{comic
| number = 2491
| date = July 20, 2021
| title = Immune Factory
| image = immune_factory.png
| titletext = In the final vote, the doubters were won over by the strength of the name IMMUNION.
}}

==Explanation==
{{incomplete|Created by an IMMUNION. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}
This comic is another entry in a [[:Category:COVID-19|series of comics]] related to the {{w|COVID-19 pandemic|2020-21 pandemic}} of the {{w|SARS-CoV-2}} virus, which causes {{w|COVID-19}}, specifically regarding the [[:Category:COVID-19 vaccine|COVID-19 vaccine]].

When [[Hairy]] received his first dose of a COVID-19 vaccine, his body began building a defense in the form of antibodies. He has now received his second shot, and is feeling even more unwell than the first time, since his body has ramped up the production of antibodies, as [[Cueball]] states. Hairy and Cueball then begins to make comments that metaphorically compare Hairy's immune system to a factory, hence the title Immune Factory.

Vaccines in general work by giving the body's immune system a chance to respond to a pathogen without actually being infected. The immune system responds by producing antibodies, proteins customised to attach to the pathogen, either disabling it directly or marking it for attack by immune cells. After the vaccine (or after an actual illness), the {{w|Immunological memory|immune system remembers}} how to make the antibodies and can more quickly respond to future infections. This is why Hairy describes his body as an "antibody factory".

However, many common symptoms of illness (such as fever, soreness, diarrhea and nausea) are actually caused by the body's immune response rather than the infection itself. As a result, vaccines can result in similar symptoms to an illness, albeit milder and of shorter duration.

Hairy extends the "body as factory" metaphor by complaining that, since he feels unwell, the factory must be violating {{w|Occupational Safety and Health Administration|OSHA}} regulations—that is, rules that protect workers from unsafe work conditions. Hairy says his {{w|lymphatic system}} (a major component of the immune system) is protesting the "brutal" work of responding to the vaccine, as human workers might protest a dangerous workplace.

In real workplaces, one possible response to worker dissatisfaction is for them to {{w|Trade union|unionize}}, forming an organization that can use their solidarity to bargain for improvements to working conditions. Hairy says that this is what his immune cells have done. It is not clear whether this corresponds to any actual part of the immune response, or whether it is simply a humorous expansion on the "factory" metaphor.

Cueball uses the "union" statement to set up a pun on two meanings of the word "scab". If unions make demands that an employer refuses, their workers may {{w|Strike action|strike}}, or refuse to work. Employers may keep the workplace running by hiring {{w|strikebreaker}}s, non-union workers (or union workers who break ranks with their colleagues). Union members may refer to strikebreakers by the pejorative term "scabs".

That perjorative meaning of "scab" is derived from the hard coating the body produces to cover a bleeding or seeping wound while it heals, which is unattractive (though biologically useful). {{w|Smallpox}} is a dangerous illness that causes ulcers upon the skin, leading to many small scabs forming as those ulcers heal. Prior to modern vaccination techniques, people were sometimes deliberately infected with smallpox—typically from a person with a mild case—while they were healthy. This process, now called {{w|variolation}} (after ''Variola'', the virus that causes smallpox), could be done in various ways.

One old method was to {{w|Insufflation (medicine)|insufflate}} (blow up their nose) the powdered scabs of a person who had been sick, introducing the material via one or other mucus membrane, but another was to create a deliberately 'messy' surface wound with a skin cutting device 'infected' with the vaccination substance. These days, the modern vaccination process usually involves a deeper injection, intramuscular, with a sharp needle that does not create significant surface scabbing and leave a life-long vaccination scar. The pun therefore is that members of the immune system union would not like ''either'' kind of scab.

The title-text parodies the trend for recent incarnations of unions to rebranded or form anew with a descriptively apt name (possibly with a forced acronym, or styled as one for branding purposes), rather than the (Extended/[https://acronyms.thefreedictionary.com/VETLA Very Extended]/etc) Three Letter Acronyms of times past. In this case making a portmanteau of Immune Union - Immunion. It is stated that this name ''seemed so strong'', that it won over the doubters in the final vote for what to call this new union.

==Transcript==
:[Cueball walks in from the left, hand held up in front of him, to where Hairy is sitting in an armchair facing away, presumably feeling sick from a second {{w|COVID-19}} vaccination. Hairy is wrapped in a blanket and holding a steaming mug, and his hair is messy.]
:Cueball: I guess the first shot made your body build defenses, and now it's ramping up production.
:Hairy: So I've become an antibody factory.

:[Cueball has walked around the chair and is now facing Hairy, whose mug continues to steam.]
:Hairy: I don't feel great. I think my factory has some OSHA violations.
:Hairy: My lymphatic system is protesting brutal working conditions.

:[In a frame-less panel, Cueball continues to stand in front of Hairy, whose mug is steaming less.]
:Hairy: Update: my immune cells have unionized.
:Cueball: Common side effect. Helps maintain a healthy balance.

:[In a panel with a frame, Cueball has raised a finger into the air, while Hairy is pointing in Cueball's direction. Hairy's mug is no longer steaming.]
:Cueball: Immune system unions are actually why we stopped doing variolation.
:Hairy: Oh? Why?
:Cueball: They don't like scabs.
:Hairy: ''Ugh. Leave.''

{{comic discussion}}

[[Category:COVID-19 vaccine]]
[[Category:COVID-19]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Hairy]]
[[Category:Portmanteau]]
[[Category:Puns]]

2491: Immune Factory

2021-07-20T16:50:08Z

172.70.98.96: /* Explanation */ better

2487: Danger Mnemonic

2021-07-13T00:54:17Z

172.70.98.96: /* Transcript */ cat

{{comic
| number = 2487
| date = July 9, 2021
| title = Danger Mnemonic
| image = danger_mnemonic.png
| titletext = It's definitely not the time to try drinking beer before liquor.
}}

==Explanation==
{{incomplete|Created by a DRUNKEN SAILOR'S POISON IVY SNAKE. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

The teacher [[Miss Lenhart]] warns two small kids using a danger {{w|mnemonic}}.

However, this is actually a mash-up of three different common danger mnemonics, which warn about three different hazards.

*Red touch black, friend of Jack; red touch yellow, kill a fellow.

This mnemonic is intended to help recognize a venomous {{w|coral snake}}, which has red, black, and yellow stripes, with the red and yellow stripes adjacent. Nonvenomous {{w|king snake}} species also have red, black, and yellow stripes, but the black stripes separate the red and yellow ones. Note that this identification is accurate only in eastern North America; coral snakes in other parts of the world sometimes have black stripes touching red stripes. The safest course of action is to avoid any snake with the warning colors of red, yellow/white, and black stripes. Another corruption of same warning features in [[1604: Snakes]].

*Leaves of three, leave them be; berries white, poisonous sight. (Alternatively, "berries white, run in fright")

This mnemonic is used to identify {{w|poison ivy}} and {{w|poison oak}} throughout much of North America. These plants both produce an oily surface resin called urushiol, which causes an allergic reaction in the majority of people. Touching either plant can result in contact dermatitis, which can be severely itchy or painful. If burned, the urushiol can be inhaled, causing lung irritation. While rarely serious, these reactions are often severely unpleasant and can last for weeks, so avoiding the plants is well advised. Both plants generally grow three leaves at the end of each branch, and grow berries that turn white when ripe. The mnemonic helps in remembering this characteristic to distinguish them from similar-looking but harmless vines. See [[443: Know Your Vines]].

*Red sky at night, sailor's delight; red sky in the morning, sailors take warning.

This {{w|Red sky at morning|mnemonic}} predicts bad/good weather conditions based on a particularly red sunrise/sunset. It is predictive at {{w|middle latitudes}} where the prevailing winds go from west to east. Regions of higher air pressure will cause a particularly red sky at sunrise/sunset, so a red sky in the evening indicates a high pressure system is coming in from the west with its calmer weather, while a red sky in the morning indicates a low pressure front coming in (usually with rain and rougher weather). In some countries (such as the United Kingdom), the saying mentions shepherds rather than sailors. Randall actually wrote a [https://www.nytimes.com/2019/08/13/science/what-makes-a-red-sky-at-night-and-at-morning.html newspaper article] explaining this phenomenon.

Combining all three sayings sounds particularly ominous. It implies that a person is involved with a situation simultaneously involving coral snakes, poison ivy, and potentially nasty weather. In such a case, Miss Lenhart advises the children to "just get out of there", implying that the situation is too dangerous to try to deal with.

The title text refers to another mnemonic: 'Beer before liquor, never been sicker; liquor before beer, you're in the clear.' Unlike the first three mnemonics, which are genuinely useful for avoiding danger, this one is [https://www.nytimes.com/2006/02/07/health/the-claim-mixing-types-of-alcohol-makes-you-sick.html largely a myth], as the order in which you drink alcohol is unlikely to impact how sick you become. However, whether the mnemonic is true or not, testing it would involve multiple drinks of alcohol, which would be ill-advised when facing a dangerous situation, particularly one as bizarre and complex as implied in this strip.

Also see [[2038: Hazard Symbol]] for another combination of danger warnings.

==Transcript==

:[Miss Lenhart is holding a finger up in front of two children: a boy with spiky hair and Science Girl.]

: Miss Lenhart: Now, remember:
: Miss Lenhart: If red touches yellow amid leaves of three under a red sky at morning,
: Miss Lenhart: You should probably just get out of there.

{{comic discussion}}

[[Category:Comics featuring Miss Lenhart]]
[[Category:Comics featuring Science Girl]]
[[Category:Food]]
[[Category:Animals]]

2487: Danger Mnemonic

2021-07-11T06:42:33Z

172.70.98.96: /* Explanation */ wlinks

{{comic
| number = 2487
| date = July 9, 2021
| title = Danger Mnemonic
| image = danger_mnemonic.png
| titletext = It's definitely not the time to try drinking beer before liquor.
}}

==Explanation==
{{incomplete|Created by a DRUNKEN SAILOR'S POISON IVY SNAKE. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

This is a mash-up of three different common sayings: "red touches yellow, dead fellow. Red touches black, happy Jack," "leaves of three, leave them be; berries white, poisonous sight" and "red sky at morning, sailors take warning. Red sky at night, sailor's delight."

The combination of the three sayings make it sound somewhat like an ominous prophecy, citing odd, specific conditions under which some unknown disaster will occur- in which case, you probably should get out of there.

The adult refers to three different sayings that remind people how to recognize dangerous things or situations. If all are true at once, then things must be especially bad. The sayings are:

*'''Red touches yellow, kills a fellow.''' This is a saying for how to recognize a venomous {{w|coral snake}}, which has red, black, and yellow stripes, with the red and yellow stripes adjacent. A nonvenomous {{w|king snake}} also has red, black, and yellow stripes, but the black stripes separate the red and yellow ones. Note that this identification is only accurate in eastern North America, coral snakes in other parts of the world sometimes have black stripes touching red stripes. The safest course of action is to avoid any snake with the warning colors of red, yellow/white, and black stripes.
*'''Leaves of three, leave them be''' is used to identify {{w|poison ivy}} (on the east coast) and {{w|poison oak}} (on the west coast) from its many lookalikes, such as the Virginia creeper in [[443: Know Your Vines]].
*'''Red sky at morning, sailor take warning.''' The {{w|Red sky at morning|mnemonic}} predicts bad/good weather conditions based on a particularly red sunrise/sunset. It is predictive at {{w|middle latitudes}} where the prevailing winds go from west to east. Regions of higher air pressure will cause a particularly red sky at sunrise/sunset, so a red sky in the evening indicates a high pressure system is coming in from the west with its calmer weather, while a red sky in the morning indicates a low pressure front coming in (usually with rain/rougher weather). In some countries (such as the United Kingdom), the saying mentions shepherds rather than sailors.

The title text refers to the myth of '''Beer before liquor, never been sicker; liquor before beer, you're in the clear''', or one of various other colloquial folk variations that clearly already inspired [[2422: Vaccine Ordering]]. Unlike the first three mnemonics which are genuinely useful for avoiding danger, this one does not have any truth behind it - unless the order affects how ''much'' you drink. Perhaps the title text is a warning against getting drunk around deadly snakes, and poison ivy, in bad weather.

Also see [[2038: Hazard Symbol]] for another combination of danger warnings.

==Transcript==

:[Blondie talking to two children: a younger looking Hairy and Science Girl]

: Blondie: Now, remember:
: Blondie: If red touches yellow amid leaves of three under a red sky at morning,
: Blondie: you should probably just get out of there.

{{comic discussion}}
[[Category:Comics featuring Blondie]]
[[Category:Comics featuring Science Girl]]

2487: Danger Mnemonic

2021-07-10T23:15:21Z

172.70.98.96: /* Explanation */ Added an important caveat about the reliability of the coral snake vs. king snake identification rhyme.

{{comic
| number = 2487
| date = July 9, 2021
| title = Danger Mnemonic
| image = danger_mnemonic.png
| titletext = It's definitely not the time to try drinking beer before liquor.
}}

==Explanation==
{{incomplete|Created by a DRUNKEN SAILOR'S POISON IVY SNAKE. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

This is a mash-up of three different common sayings: "red touches yellow, dead fellow. Red touches black, happy Jack," "leaves of three, leave them be; berries white, poisonous sight" and "red sky at morning, sailors take warning. Red sky at night, sailor's delight."

The combination of the three sayings make it sound somewhat like an ominous prophecy, citing odd, specific conditions under which some unknown disaster will occur- in which case, you probably should get out of there.

The adult refers to three different sayings that remind people how to recognize dangerous things or situations. If all are true at once, then things must be especially bad. The sayings are:

*'''Red touches yellow, kills a fellow.''' This is a saying for how to recognize a venomous coral snake, which has red, black, and yellow stripes, with the red and yellow stripes adjacent. A nonvenomous king snake also has red, black, and yellow stripes, but the black stripes separate the red and yellow ones. Note that this identification is only accurate in eastern North America, coral snakes in other parts of the world sometimes have black stripes touching red stripes. The safest course of action is to avoid any snake with the warning colors of red, yellow/white, and black bans.
*'''Leaves of three, leave them be''' is used to identify poison ivy (on the east coast) and poison oak (on the west coast) from its many lookalikes, such as the Virginia creeper in [[443: Know Your Vines]].
*'''Red sky at morning, sailor take warning.''' The {{w|Red sky at morning|mnemonic}} predicts bad/good weather conditions based on a particularly red sunrise/sunset. It is predictive at {{w|middle latitudes}} where the prevailing winds go from west to east. Regions of higher air pressure will cause a particularly red sky at sunrise/sunset, so a red sky in the evening indicates a high pressure system is coming in from the west with its calmer weather, while a red sky in the morning indicates a low pressure front coming in (usually with rain/rougher weather). In some countries (such as the United Kingdom), the saying mentions shepherds rather than sailors.

The title text refers to the myth of '''Beer before liquor, never been sicker; liquor before beer, you're in the clear''', or one of various other colloquial folk variations that clearly already inspired [[2422: Vaccine Ordering]]. Unlike the first three mnemonics which are genuinely useful for avoiding danger, this one does not have any truth behind it - unless the order affects how ''much'' you drink. Perhaps the title text is a warning against getting drunk around deadly snakes, and poison ivy, in bad weather.

Also see [[2038: Hazard Symbol]] for another combination of danger warnings.

==Transcript==

:[Blondie talking to two children: a younger looking Hairy and Science Girl]

: Blondie: Now, remember:
: Blondie: If red touches yellow amid leaves of three under a red sky at morning,
: Blondie: you should probably just get out of there.

{{comic discussion}}
[[Category:Comics featuring Blondie]]