explain xkcd - User contributions [en]

Talk:710: Collatz Conjecture

2024-03-26T16:04:46Z

Boochin:

Technically, the 1 should lead to the four, causeing a loop. Because (1*3)+1=4, 4/2=2, 2/2=1 xD {{unsigned|‎87.242.215.66}}
:I'm pretty sure (follow the Wiki link, perhaps, although I haven't yet) there's an implicit "...eventually lead to one, then you can stop" for this process.
:And (again without checking the Wiki link), I suppose the conjecture could fail in one of two cases. Firstly if multiplying by three and adding one would take us to another odd number. Which cannot happen, because (odd*3) will be odd, so (odd*3)+1 is even. Which leads us to the possibility that the even number leads back to a prior odd number, to circle around again. There's no trivial case of (n*3)+1 => m, (m/2) => n, although there is the case of (n*3)+1 => m, (m/2) => o, (o/2) => n, for n=1. How, though, could we evaluate f1|2(xi) => xi+1 for all countably finite limits to i, given the rules of which f() function to use, to ensure that xi never equals x0. Now, ''that's'' a question and a half. Which I suspect has already been asked. And a half. [[Special:Contributions/31.111.50.225|31.111.50.225]] 21:36, 7 May 2013 (UTC)
:: Wonderful! "Without checking the wiki link"... The guy from [[675: Revolutionary]] in real life![[User:Mumiemonstret|Mumiemonstret]] ([[User talk:Mumiemonstret|talk]]) 15:14, 17 October 2014 (UTC)
::: It's pretty obvious the person you replied to has a head for mathematics. If you really think this is at all similar to the Goatee Guy from [[675: Revolutionary]], then you are sorely mistaken. [[Special:Contributions/172.68.59.84|172.68.59.84]] 13:40, 22 November 2018 (UTC)
:: It seems way too general to be much more than "asked," and I am sure that it has been addressed in its simpler forms. In any case, there is enough amateur, recreational, and serious mathematical literature on it to find out that there are indeed two failure cases: a starting Collatz number results in an infinitely increasing sequence, or a loop exists apart from the 4-2-1 loop. (Curiously enough, some loops exist when negative numbers are allowed.) Stuff like this and Goldbach made me realize just how hard simple things can get. --[[User:Quicksilver|Quicksilver]] ([[User talk:Quicksilver|talk]]) 03:04, 20 August 2013 (UTC)
:: A way to ask if the trajectory eventually reach 1 is to ask if the number is increasing or decreasing. If it is decreasing, it will eventually his a number already confirmed earlier to be on the trajectory. Whenever (n*3 + 1) is applied, the result is always even, and must be divided by two. But (n*3 + 1) / 2 > n. So the value will increase unless it hit a positive value more often than every other time. If it hit even 2 out of 3 times, the value decrease as (n*3 + 1) / (2*2) < n for all values of n > 1.
::The show can go on until it eventually hit a number m for which it is true that m = 2^x for some positive integer x. This value will take it all the way to the bottom. So the way the conjecture can be untrue is if some kind of loop exist, which either blow up the value towards infinity without ever hitting a 2^x number, or just forms a loop which bring it back to previous values. Again this can only be true if no 2^x number is ever reached. [[User:MigB|MigB]] ([[User talk:MigB|talk]]) 11:41, 13 April 2021 (UTC)

Just for fun, here's 710's Collatz Trajectory.
0: 710
1: 355
2: 1066
3: 533
4: 1600
5: 800
6: 400
7: 200
8: 100
9: 50
10: 25
11: 76
12: 38
13: 19
14: 58
15: 29
16: 88
17: 44
18: 22
19: 11
20: 34
21: 17
22: 52
23: 26
24: 13
25: 40
26: 20
27: 10
28: 5
29: 16
30: 8
31: 4
32: 2
33: 1
[[User:International Space Station|International Space Station]] ([[User talk:International Space Station|talk]]) 09:36, 25 January 2016 (UTC)

I wrote a program to calculate the tree (Python 3.9), but you have to install treelib. Do this by typing 'pip install treelib' in the terminal. The program:

from treelib import *
tree=Tree()
levels=int(input('Levels of tree? '))
start=int(input('Starting number? '))
tree.create_node(start, start)
def f(x):
global tree
if tree.depth(x)==tree.depth():
return True
else:
return False
def collatz(x):
if x%2==0 and x%3==1 and x!=4:
return [(x-1)//3,x*2]
else:
return [x*2]
for i in range(levels):
N = list(tree.filter_nodes(f))
for i in N:
c=collatz(i.tag)
for j in c:
tree.create_node(j,j,i)
tree.show(line_type='ascii-ex')

--[[Special:Contributions/198.41.238.106|198.41.238.106]] 01:31, 28 July 2021 (UTC)

:If we're sharing code, I made a Python script that calculates a string for any given number and then graphs it:

import matplotlib.pyplot as plt
start_number = int(input("Enter a number:\n"))
loop_count = 0
full_list = [start_number]
while start_number != 1:
loop_count += 1
if start_number % 2 == 0:
start_number = int(start_number / 2)
print(start_number)
full_list.append(start_number)
elif start_number % 2 == 1:
start_number = int(start_number * 3 + 1)
print(start_number)
full_list.append(start_number)
else:
print("Error")
print("Iterations: " + str(loop_count))
plt.plot(full_list)
plt.title('Graph (Linear)')
plt.xlabel('Steps')
plt.ylabel('Hight')
plt.show()

Talk:710: Collatz Conjecture

2024-03-26T16:04:08Z

Boochin:

Technically, the 1 should lead to the four, causeing a loop. Because (1*3)+1=4, 4/2=2, 2/2=1 xD {{unsigned|‎87.242.215.66}}
:I'm pretty sure (follow the Wiki link, perhaps, although I haven't yet) there's an implicit "...eventually lead to one, then you can stop" for this process.
:And (again without checking the Wiki link), I suppose the conjecture could fail in one of two cases. Firstly if multiplying by three and adding one would take us to another odd number. Which cannot happen, because (odd*3) will be odd, so (odd*3)+1 is even. Which leads us to the possibility that the even number leads back to a prior odd number, to circle around again. There's no trivial case of (n*3)+1 => m, (m/2) => n, although there is the case of (n*3)+1 => m, (m/2) => o, (o/2) => n, for n=1. How, though, could we evaluate f1|2(xi) => xi+1 for all countably finite limits to i, given the rules of which f() function to use, to ensure that xi never equals x0. Now, ''that's'' a question and a half. Which I suspect has already been asked. And a half. [[Special:Contributions/31.111.50.225|31.111.50.225]] 21:36, 7 May 2013 (UTC)
:: Wonderful! "Without checking the wiki link"... The guy from [[675: Revolutionary]] in real life![[User:Mumiemonstret|Mumiemonstret]] ([[User talk:Mumiemonstret|talk]]) 15:14, 17 October 2014 (UTC)
::: It's pretty obvious the person you replied to has a head for mathematics. If you really think this is at all similar to the Goatee Guy from [[675: Revolutionary]], then you are sorely mistaken. [[Special:Contributions/172.68.59.84|172.68.59.84]] 13:40, 22 November 2018 (UTC)
:: It seems way too general to be much more than "asked," and I am sure that it has been addressed in its simpler forms. In any case, there is enough amateur, recreational, and serious mathematical literature on it to find out that there are indeed two failure cases: a starting Collatz number results in an infinitely increasing sequence, or a loop exists apart from the 4-2-1 loop. (Curiously enough, some loops exist when negative numbers are allowed.) Stuff like this and Goldbach made me realize just how hard simple things can get. --[[User:Quicksilver|Quicksilver]] ([[User talk:Quicksilver|talk]]) 03:04, 20 August 2013 (UTC)
:: A way to ask if the trajectory eventually reach 1 is to ask if the number is increasing or decreasing. If it is decreasing, it will eventually his a number already confirmed earlier to be on the trajectory. Whenever (n*3 + 1) is applied, the result is always even, and must be divided by two. But (n*3 + 1) / 2 > n. So the value will increase unless it hit a positive value more often than every other time. If it hit even 2 out of 3 times, the value decrease as (n*3 + 1) / (2*2) < n for all values of n > 1.
::The show can go on until it eventually hit a number m for which it is true that m = 2^x for some positive integer x. This value will take it all the way to the bottom. So the way the conjecture can be untrue is if some kind of loop exist, which either blow up the value towards infinity without ever hitting a 2^x number, or just forms a loop which bring it back to previous values. Again this can only be true if no 2^x number is ever reached. [[User:MigB|MigB]] ([[User talk:MigB|talk]]) 11:41, 13 April 2021 (UTC)

Just for fun, here's 710's Collatz Trajectory.
0: 710
1: 355
2: 1066
3: 533
4: 1600
5: 800
6: 400
7: 200
8: 100
9: 50
10: 25
11: 76
12: 38
13: 19
14: 58
15: 29
16: 88
17: 44
18: 22
19: 11
20: 34
21: 17
22: 52
23: 26
24: 13
25: 40
26: 20
27: 10
28: 5
29: 16
30: 8
31: 4
32: 2
33: 1
[[User:International Space Station|International Space Station]] ([[User talk:International Space Station|talk]]) 09:36, 25 January 2016 (UTC)

I wrote a program to calculate the tree (Python 3.9), but you have to install treelib. Do this by typing 'pip install treelib' in the terminal. The program:

from treelib import *
tree=Tree()
levels=int(input('Levels of tree? '))
start=int(input('Starting number? '))
tree.create_node(start, start)
def f(x):
global tree
if tree.depth(x)==tree.depth():
return True
else:
return False
def collatz(x):
if x%2==0 and x%3==1 and x!=4:
return [(x-1)//3,x*2]
else:
return [x*2]
for i in range(levels):
N = list(tree.filter_nodes(f))
for i in N:
c=collatz(i.tag)
for j in c:
tree.create_node(j,j,i)
tree.show(line_type='ascii-ex')

--[[Special:Contributions/198.41.238.106|198.41.238.106]] 01:31, 28 July 2021 (UTC)

:If we're sharing code, I made a Python script that calculates a string for any given number and then graphs it:

import matplotlib.pyplot as plt

start_number = int(input("Enter a number:\n"))
loop_count = 0
full_list = [start_number]

while start_number != 1:
loop_count += 1
if start_number % 2 == 0:
start_number = int(start_number / 2)
print(start_number)
full_list.append(start_number)
elif start_number % 2 == 1:
start_number = int(start_number * 3 + 1)
print(start_number)
full_list.append(start_number)
else:
print("Error")

print("Iterations: " + str(loop_count))
plt.plot(full_list)

plt.title('Graph (Linear)')
plt.xlabel('Steps')
plt.ylabel('Hight')

plt.show()

2894: Research Account

2024-02-16T22:34:14Z

Boochin: /* Explanation */

{{comic
| number = 2894
| date = February 14, 2024
| title = Research Account
| image = research_account_2x.png
| imagesize = 291x479px
| noexpand = true
| titletext = Focus of your research: EXTREME PETTINESS AND UNWILLINGNESS TO LET ANYTHING GO
}}

==Explanation==
{{incomplete|Created by a BOT THAT WILL ARGUE WITHOUT MERCY - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

[[Cueball]] has a longstanding craving to win online arguments and to prioritize these arguments (see [[386: Duty Calls]], one of Randall's viral comics). In the comic he is filling out a form to register for a research account. Such accounts are typically intended for people doing serious work in the relevant field, who need access to the materials provided to support that work. Cueball, however, has filled out “other/none” for institution, and “to win an argument with someone in a group chat” for “reason for requesting access to our datasets”, making it clear that his interest is both petty and personal. While this may be honest, it doesn't match the assumed purpose, and he may be worried that it might mean that his registration would be rejected or subsequently cancelled. So he then selects all and deletes his previous justification, replacing it with “independent research”, which is an accurate, if generic, explanation. Randall is undoubtedly familiar with such registration forms from doing background research for xkcd and What If?.

In the title text, he says that his research focuses on “extreme pettiness and unwillingness to let anything go” (in all caps), further reinforcing the reason that he is doing this solely to win an argument. It is possible this is a pun on different meanings of the word "focus" - while the question about the focus of one's research is typically about the subject matter they are researching (raft building in fire ants, etc), Cueball appears to be writing about what drives his desire to do research. Similarly, Cueball is not doing research INTO pettiness, but rather is focusing entirely on his pettiness as his main reason to perform research and achieve his goals. Of course, there is a focused area of research related to individuals who obsessively pursue matters disproportionately to their severity, who are known as {{w|querulant|querulants}}.

It is not uncommon for online forms to include fields like these, where it's unclear what, if anything, will be done with the input, and therefore how much it matters what is entered. It's unlikely that anyone would have the capacity to review all the freetext answers submitted, and in any case, by the time they did so, Cueball would presumably have already accessed the materials he wanted.

==Transcript==

:[Cueball sits at a desk, typing at his laptop computer.]

:[Above him, there is a box indicating his computer screen.]

:[Caption above screen:] Application for research account

:[Under the caption, there is a panel, representing the computer screen; in the panel: (cut off from above) "Institution: Other/none", where the option has been selected from a drop-down menu. Under that is written "Reason for requesting access to our datasets:", under which is a comment field where "To win an argument with someone in a group chat" has been written. Under that, two long bubbles containing the words "Select all" and "Delete" separate another panel, with a panel featuring the comment field with "Independent research" written. The cursor can still be seen blinking.]

:[Caption below the comic panel:]
:I never know how honest to be on these forms.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Science]]

Talk:2894: Research Account

2024-02-16T22:32:54Z

Boochin:

wasn't there a whatif that caused Randal to temporally loose the access to Wolfram Alpha?
[[Special:Contributions/172.70.175.26|172.70.175.26]] 19:40, 14 February 2024 (UTC)
:It was [https://what-if.xkcd.com/62/ the what if about balloons] [[User:Anonymouscript|Anonymouscript]] ([[User talk:Anonymouscript|talk]]) 02:02, 15 February 2024 (UTC)
Although Cueball is often considered to be Randall's alter ego in the comics, when writing explanations we refer to the character. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 20:16, 14 February 2024 (UTC)

I wanted to add something to the explanation saying that he's overthinking, and it probably doesn't matter what you write in the justification, since it's unlikely that anyone actually reads them. But I don't actually know this. If anyone knows what goes on behind the scenes at research institutions, add something. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 20:23, 14 February 2024 (UTC)
:That's my impression (it's very like an account-creation process, supplying free-text to be reviewed at leisure only after attaching the user to a UID with no more verification other than "click on this emailed link to confirm this is your contact details", rather than an application which can be denied or blackballed). But I don't delve into (or control) particularly privileged data-sources where it could be far more strict (yet not so much that it can't be handled by an easy to access web-form), so would also be interested in hearing the facts-of-life from beyond the more open-data side of things. [[Special:Contributions/172.69.194.60|172.69.194.60]] 22:32, 14 February 2024 (UTC)
:I suspect the "Institution" dropdown might be used for some marketing statistics. No one has time to go through all the free-form inputs, although AI may change that. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 22:58, 14 February 2024 (UTC)
::If the database is being funded by a grant (governmental or philanthropic), the "institution" data are likely reported back to the funder, as a means of assessing whether the database is reaching the targeted audience, as may be specified on the proposal. Not too far from "marketing statistics", I reckon. A larger-than-expected number of non-institutional users, especially if the database is targeted to a small number of highly specialized users, could trigger more scrutiny of "reasons for" comments. Such scrutiny could have more direct impact on the grantee (imposition of more restricted access, or grant termination) than on the individual user. [[Special:Contributions/172.71.142.21|172.71.142.21]] 05:53, 15 February 2024 (UTC)

I would say there's also some similarity to the classic [https://xkcd.com/386/ 386: Duty Calls]. --[[Special:Contributions/108.162.245.248|108.162.245.248]] 03:35, 15 February 2024 (UTC)
:Definitely. I didn't even recognize it by the title, but I just pulled it up in reference to my own behavior patterns... Cueball looks like he's barely moved since then!
:[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 01:56, 16 February 2024 (UTC)

Reading this comic, I feel attacked
[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 18:30, 15 February 2024 (UTC)
:You could probably get away with calling it "Combating public misinformation."
:[[Special:Contributions/172.71.182.57|172.71.182.57]] 22:37, 15 February 2024 (UTC)
::[https://www.explainxkcd.com/wiki/index.php/386:_Duty_Calls Duty calls...]
::[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 01:56, 16 February 2024 (UTC)
::"Educational outreach". Might be funny with effectively "no organisation", if they have "university", "college", "high school", "elementary school", as actual choices. But, without seeing what the rest of the drop-down options are, might still be conceivably a valid reasoning to have "other" (get them wondering if you mean to educate a kindergarten class/a scout troop/a prison educational program/whatever). [[Special:Contributions/172.69.194.162|172.69.194.162]] 02:55, 16 February 2024 (UTC)

The part about "spell focus" seems unnecessary and unrelated. I'm going to delete it if no one objects. [[User:Boochin|Boochin]] ([[User talk:Boochin|talk]]) 22:32, 16 February 2024 (UTC)

194: Penises

2023-11-02T07:55:01Z

Boochin: Removed a dumb "citation needed" joke.

{{comic
| number = 194
| date = December 8, 2006
| title = Penises
| image = penises.png
| titletext = The penis varies in size when flaccid and is pretty consistently about yea big when erect. Anyway, back to the sitcom one-liners and the constant flow of spam.
}}
==Explanation==
The comic takes aim at what is considered by some to be the apparent societal obsession with the {{w|human penis|male sexual organ}} ("phallocentrism"), especially in regard to size. In general, depictions of an erect penis (also called {{w|phallus}}) represent male potency.

While present in every human civilization, the symbol of the penis is also prominently featured in modern mass media. Many films and television series make use of penis-related jokes. A very common trope is the male obsession with the idea that a larger penis is considered more desirable, and a smaller penis less manly or satisfying to women.

Megan criticizes this obsession by pointing out that most penises are about the same size, and normal variations in size are not worth getting worked up about.

The title text refers to the excessive advertisement for {{w|Sildenafil|potency pills}} and {{w|penis enlargement}} in {{w|Email spam|spam emails}}. The symbol of the phallus can be regarded by some as omnipresent in modern Western society (but not necessarily in other cultures), with presumably every public toilet sporting at least one badly drawn depiction of a penis.

==Transcript==
:PENISES:
:Megan: They are about this big.
:[Holds her hands close together, about half a foot apart.]
:Now can we PLEASE, as a culture, move on?

{{comic discussion}}
[[Category:Comics featuring Megan‏‎]]
[[Category:Penis]]

1963: Namespace Land Rush

2023-10-30T08:03:56Z

Boochin: /* Explanation */

{{comic
| number = 1963
| date = March 5, 2018
| title = Namespace Land Rush
| image = namespace_land_rush.png
| titletext = You can also just mash the keyboard at random, but you might end up with a gibberish name no one can pronounce.
}}

==Explanation==

When a new web service starts, such as a forum, a social media server or an email portal, the people who sign up get to choose their username on the service, which, in most cases, blocks future users from using those usernames. Common names such as "john" are likely to be taken quickly.

This comic is a list of usernames [[Randall]] suggests should be used if they are available.

The title text is a self-reference to "xkcd"; the name of the comic is a purposefully unpronounceable phrase created by Randall. The fact that an unpronounceable name is portrayed as a disadvantageous outcome is also humorous because the comic has a section dedicated to unpronounceable usernames.

(Note: for a more serious list of problematic user names to block from a service provider’s point of view, see [https://ldpreload.com/blog/names-to-reserve Hostnames and usernames to reserve] as well as [https://tools.ietf.org/html/rfc2142 RFC 2142].)

==Table==
{| class="wikitable"
!style="width:30%"|Entry
!style="width:70%"|Explanation
|-
!colspan=2|Straightforward (Usernames that a person would use under typical circumstances)
|-
|<Your usual username, if any>
|Most internet users will have settled on some unique handle that they try to use across all platforms. Even if this wasn't a new service, most people would try this first.
|-
|<Your given name>
|More rare is using one's nickname or first name as their username, since the amount of common names will mean many users share a name. Thus, if you can get your given name, you will have a simple username that many others wanted, and without resorting to prefixes or numbers (i.e. Xx_MyName00_xX)
|-
|<Your full name>
|Similar to your given name, but slightly more unique since a last name and/or middle name is added.
|-
|<Initial><Surname>
|A common second choice if a given or full name is already in use.
|-
|<Surname>
|Possibly available if your last name is more uncommon; names like "Smith" or "Kim" will probably be taken faster than even given names.
|-
!colspan=2|Recognizable (Usernames that would make it look like the email came from an official source within the organization named)
|-
|Google
|Registering the name "Google" would allow for communicating on the site (or even outside of it) with a name that appears to be an official Google account. For any of the examples in this section, you would select the names for the same reason. This has been done in the past with both [https://twitter.com/BiIIMurray humorous] and [http://www.chicagotribune.com/bluesky/technology/ct-russian-twitter-account-tennessee-gop-20171018-story.html nefarious] results.
|-
|iPhone
|Many services would mark messages sent from an iOS client on iPhone as "sent from iPhone".
This could make people believe that your messages are sent from an iPhone even if you don't own one.
|-
|Facebook
|Similar to Google above.
|-
|Bitcoin
|One could pose as the Bitcoin Core development group by using this handle and/or scam uninformed users interested in cryptocurrencies.
|-
|Obama
|Impersonating the former president, supposedly to send messages as them to make them seem bad (or not).
|-
|Canada
|Impersonating a whole country might get you in trouble.{{Citation needed}}
|-
|NFL
|The American "National Football League".
|-
|Garfield
|In the original "GMail" service on the Internet, the G stood for "Garfield".
|-
|<Your city>
|Impersonating the official account for your place of residence.
|-
|NASA
|The American "National Aeronautics and Space Administration". Randall worked there as a contract programmer and roboticist.
|-
|<Name of person who runs the service>
|Impersonating the site owner can allow you to gain the trust of users.
|-
!colspan=3|Causing Trouble (Usernames that might cause errors when mixed with the service's back-end code)
|-
|User
|This is usually the default username for a non-administrative account. This may trick a user that this is owned by the operator of the service.
|-
|Username
|See above.
|-
|Name
|See above.
|-
|You
|Many services display "You" as the signed-on user, so naming oneself "You" makes users think that they are you/they are signed on when they aren't.
|-
|Guest
|Attempts to fool users into thinking that they have a guest account.
|-
|Account
|The opposite of "Guest" (someone without an account). However, for someone with an account, their username will usually be displayed. There is an active user named "Account" on Explain XKCD.
|-
!colspan=2|Causing More Trouble
|-
|Admin
|Impersonating to be a system administrator will let someone fool people and cause a lot of trouble. In particular, it could be used to obtain SSL certificates by demonstrating ownership of a supposedly internal address.
|-
|Administrator
|See above.
|-
|System
|Pretending to be a system-controlled account - might give permissions if the server checks by name.
|-
|<Name of service>
|Pretending to be the official account of the service. There are a lot of spammers who did this on Explain XKCD.
|-
|Help
|Pretending to be the help account. This could lead to many questions from new users.
|-
|Error
|This may trick users to do what the user says as they could claim that it was a legitimate error.
|-
!colspan=2|Impossible to Say
|-
|Hyphen-Emdash
|Could be read "Hyphen hyphen Em dash" or "Hyphen dash em dash". In addition, in many markup languages (such as the one used by this very wiki) one can create a larger hyphen with some variation of an "&mdash" command, which could theoretically be pronounced "emdash."
|-
|Dash-8hyphen-8
|Could be read "Dash dash eight hyphen dash eight" or "Dash hyphen eight hyphen hyphen eight". "Hyphen eight" sounds like "hyphenate".
|-
|Zero0ne2numeral2
|Could be read "Zero zero one two numeral two" or "Zero zero ne two numeral two" or "Zero oh ne two numeral two".
|-
|KrisasinHemsworth
|This would be confusing to say out loud, as it would sound like the user was saying that their username was "Chris," spelled the same way that famous actor {{w|Chris Hemsworth}} spells his name. However, the actual username uses the name "Kris," spelled a completely different way than Chris Hemsworth's name, and the phrase "as in Hemsworth" being also part of the username, rather than a clarification of the spelling of "Kris" as would be assumed.
|-
|TheWord&Ampersand
|This would also be confusing and difficult to communicate, as anyone trying to read the username to someone else would say "The word ampersand ampersand" which could be interpreted as "ampersand&" or "ampersand ampersand". Having the phrase "the word" in front of a symbol makes it quite difficult to communicate which variation of ampersand (word or symbol) is actually being referred to.
|-
|ZettaWith3Teees 
|Read aloud, this would lead the listener to expect a username of 'Zettta'. Clarifying that "with three tees" is text and not description would in turn make it difficult to explain the spelling of 'Zetta' with two 't's, and 'Teees' with three 'e's.
|-
!colspan=2|Misc
|-
|<Single Letters> and <Single Numbers>
|These are highly valuable. The Twitter handle "@n" for example is constantly bombarded with offers and hacking attempts.
|-
|<Common Words>
|Also highly valuable; overlaps with "Recognizable" and "Causing (more) Trouble".
|-
|<SQL/JS Injection>
|Codes such as "Drop Table" intended to cause errors or even damage the service's back-end code. (See [[327|Comic 327]])
|-
|ASDF and QWERTY
|Since those keys are right next to each other (on English language layouts), they are often typed as placeholders.
|-
|Yes
|This might be a [[Beret Guy]]-esque misunderstanding when filling out the sign up form. When encountering the form field "Username:" someone may type "Yes" (as in "yes, I want a username") instead of specifying it.
|-
|Bot and Computer
|Pretending to be a bot.
|-
|Blocked
|When users get banned or blocked, their name is often replaced by a string like this.
|-
|Deleted
|Some services like Reddit keep up user posts and data after account deletion, marking the content as submitted by the user "[Deleted]" or "Deleted".
|-
|Jeeves
|Might refer to {{w|Ask Jeeves}} (now Ask.com), a Internet Search Engine.
|-
|Narrator
|In books, radio plays and movies it is quite common to have a narrator explain parts of the story. In an online forum however, it is not.{{Citation needed}}
|-
|Internet
|"The Internet" sometimes refers to a large group of users, the collective hive-mind if you will. However, there cannot be a single user account speaking on behalf of them, as they aren't a single entity.
|-
|NPC
|Stands for Non-player character.
|-
|Password
|If the user accidentally typed their password into the username field, this would be the result.
|-
!colspan=2|Permissive Character Sets
|-
|<Space>
|Usernames containing only whitespace can not only be confusing for other people, but often systems 'trim' (remove whitespace at the beginning and end) user input. If the username was only made of spaces, after trimming it would be completely empty, which can cause a whole slew of other problems.
|-
|<nowiki>@ é |</nowiki>
|The @ separates the local part from the domain part of email addresses. If a service decides to create email addresses for their users, they will have a hard time if they allowed the "at" character as part of a username.
é is encoded in many character sets, like Latin-1 and Unicode. In Unicode, it can even be described either "U+00E9 LATIN SMALL LETTER E WITH ACUTE" or as the sequence "U+0065 LATIN SMALL LETTER E" and "U+0301 COMBINING ACUTE ACCENT". If a system uses {{w|Unicode normalization}} after the check if the username is available, this might allow someone to take over someone else's account.
|-
|<nowiki>“ ” " ‘ ’ ' `</nowiki>
|Various quotation marks.
“, ”,‘ and ’ (Unicode quotes): can expose a system's inability to handle multi-byte-encodings. If they are converted to their ASCII counterparts, they might cause code injections.
' and " (ASCII single and double quotes): often used as string delimeter (causing the rest of the name to be interpreted as HTML, or worse, code.
` (ASCII grave / backtick): Sometimes used as string delimeter; Perl (which some websites are still programmed in) executes commands ("shell code") when between backticks.
|-
|<NBSP>
|Unicode character "U+00A0 NO-BREAK SPACE". Similar attack vector as <Space>, but some programming languages will not strip non-ASCII whitespace (therefore the validation will pass).
|-
|<nowiki>\ . #</nowiki>
|The backslash is very often used for "escape sequences", that get expanded to other characters. (\n -> newline, \t -> tab character, \b -> backspace character (deletes the character to its left), etc.)
The period can be problematic in emails. RFC 2822 forbids periods at the beginning or end of the local part or more than one period in a row.
In URLs, the Octothorpe (#) is used as the 'anchor'. Anything following a # will not be transmitted to the server. If a user is named 'logout#blahblah' (which might be a valid username) and the user profile is located at http://example.com/<the_username>, the server might generate the URL http://example.com/logout#blahblah. Since the URL will be truncated at the '#', any user attempting to view this profile will be logged out of the service.
|-
|<RTL override>
|The right to left override is an Unicode character which forces text after it to be laid out right to left. Thus, in left-to-right locales, it flips everything after it. This can be rather amusing if permitted. (See [[1137|Comic 1137]])
|-
|<nowiki>– - _ /</nowiki>
|Includes both the em-dash and the hyphen, which are easily confused and are highly unusual for user names. The forward slash is also the path delimeter for URLs; if user profiles are located at e.g. <nowiki>http://example.com/user/the_username</nowiki>, this can cause obvious issues. Explain XKCD does not allow <code>/</code> in usernames.
|-
|<Any emoji>
|Current databases are not set up to store emojis as characters. Explain XKCD does allow emoji in usernames. {{actual citation needed}}
|-
|","
|In CSV files this separates one column or data item from another. This could cause bugs if the usernames are used as part of a CSV file since the next column on the row could be left blank filled with other data.
|-
|<nowiki>&NBSP</nowiki>;
|The special entity in HTML (web page language) for a non-breaking space, or a space that prevents an automatic line-break at its position. When rendered as part of an HTML page without sanitization, this would only display a space. However, if the username in question is really long, this would increase the page's width (details needed).
|-
|<nowiki></HTML></nowiki>
|This is trying to inject code for the web page using the user name. If the user name is not sanitized and does not have special characters encoded, this HTML end tag could end the HTML document, leading to page errors.
|-
|&LT;/HTML&GT;
|&lt; and &gt; are special character entities in HTML that represent < and >, repectively. So all together, when rendered as part of an HTML document, this would print "<nowiki></HTML></nowiki>" Although this would look similar to the previous <nowiki></HTML></nowiki> entry, it would be unlikely to cause problems as the symbols are not interpreted if encoded as special entities.
|-
|OkThisIsKindOfConfusingButIt's <LessThan\ForwardSlashHTML GreaterThanActualGreaterThan Symbol>Yes,ThatWasAllPartOfThe Name,ButSoIs...Ok,LetMeStartOver”
|The abundance of symbols and symbol related worlds and phrases such as ActualGreaterThanSymbol would make this extremely difficult to vocally communicate to another person. This difficulty is further compounded by the parts at the beginning and end, which sound like they are part of the explanation despite being part of the name itself.
|-
|}

==Transcript==
'''Namespace Land Rush Cheat Sheet'''
(Note: if an item is "quoted", it is meant literally, otherwise the reader is supposed to substitute their own information for words in <angle brackets>)

When a new service appears that lets you register a name, here are some you may want to try and get first:

* Straightforward
** <Your usual username, if any>
** <Your given name>
** <Your full name>
** <Initial><Surname>
** <Surname> (Bold & Slightly Unconventional)

* Recognizable
** "Google"
** "iPhone"
** "Facebook"
** "BitCoin"
** "Obama"
** "Canada"
** "NFL"
** "Garfield"
** <Your city>
** "NASA"
** <Name of person who runs the service>

* Causing Trouble
** "User"
** "Username"
** "Name"
** "You"
** "Guest"
** "Account"

* Causing More Trouble
** "Admin"
** "Administrator"
** "System"
** <Name of service>
** "Help"
** "Error"

* Impossible to Say
** "Hyphen-Emdash"
** "Dash-8hyphen-8"
** "Zero0ne2numeral2"
** "KrisasinHemsworth"
** "TheWord&Ampersand"
** "ZettaWith3Teees" 

* Misc
** <Single Letters>
** <Single Numbers>
** <Common Words>
** <SQL/JS Injection>
** "ASDF"
** "QWERTY"
** "Yes"
** "Bot"
** "Computer"
** "Blocked"
** "Deleted"
** "Jeeves"
** "Narrator"
** "Internet"
** "NPC"
** "Password"

* Permissive Character Sets
** <Space>
** <NBSP>
** <RTL override>
** <Any emoji>
** "<nowiki>&NBSP</nowiki>;"
** "<nowiki></HTML></nowiki>"
** "&LT;/HTML&GT;"
** one or more of the following symbols: <nowiki>@ é | “ ” \ . # " ‘ – - _ / ’ ' `</nowiki>
** "," (including quote marks)
** "OkThisIsKindOfConfusingButIt's<LessThan\ForwardSlashHTMLGreaterThanActualGreaterThanSymbol>Yes,ThatWasAllPartOfTheName,ButSoIs...Ok,LetMeStartOver”"

{{comic discussion}}
[[Category:Comics_with_lowercase_text]] 
[[Category:iOS]]
[[Category:Internet]]

2809: Moon

2023-08-01T01:55:35Z

Boochin:

{{comic
| number = 2809
| date = July 31, 2023
| title = Moon
| image = moon_2x.png
| imagesize = 313x402px
| noexpand = true
| titletext = I mean, it's pretty, but it doesn't really affect us beyond that. Except that half the nights aren't really dark, and once or twice a day it makes the oceans flood the coasts.
}}

==Explanation==
{{incomplete|Created by a STRANGE ORB FLOATING IN THE SKY. Do NOT delete this tag too soon.}}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
[Ponytail points to something in the sky. Cueball stands nearby]

Ponytail: That thing hanging in the sky is a second nearby world. It's close enough that you can see its surface as it passes overhead.

Cueball: Wow. Isn't that... weird?

Ponytail: I dunno, it's just always been there.

[Caption below the panel:]

If it didn't exist, the moon would sound like such an outlandish sci-fi concept.
{{comic discussion}}

2809: Moon

2023-08-01T01:55:08Z

Boochin:

{{comic
| number = 2809
| date = July 31, 2023
| title = Moon
| image = moon_2x.png
| imagesize = 313x402px
| noexpand = true
| titletext = I mean, it's pretty, but it doesn't really affect us beyond that. Except that half the nights aren't really dark, and once or twice a day it makes the oceans flood the coasts.
}}

==Explanation==
{{incomplete|Created by a STRANGE ORB FLOATING IN THE SKY. Do NOT delete this tag too soon.}}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
[Ponytail points to something in the sky. Cueball stands nearby]
Ponytail: That thing hanging in the sky is a second nearby world. It's close enough that you can see its surface as it passes overhead.
Cueball: Wow. Isn't that... weird?
Ponytail: I dunno, it's just always been there.

[Caption below the panel:]
If it didn't exist, the moon would sound like such an outlandish sci-fi concept.
{{comic discussion}}

2809: Moon

2023-08-01T01:54:12Z

Boochin:

2809: Moon

2023-08-01T01:53:37Z

Boochin:

{{comic
| number = 2809
| date = July 31, 2023
| title = Moon
| image = moon_2x.png
| imagesize = 313x402px
| noexpand = true
| titletext = I mean, it's pretty, but it doesn't really affect us beyond that. Except that half the nights aren't really dark, and once or twice a day it makes the oceans flood the coasts.
}}

==Explanation==
{{incomplete|Created by a STRANGE ORB FLOATING IN THE SKY. Do NOT delete this tag too soon.}}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
[Ponytail points to something in the sky. Cueball stands nearby]
Ponytail: That thing hanging in the sky is a second nearby world. It's close enough that you can see its surface as it passes overhead.
Cueball: Wow. Isn't that... weird?
Ponytail: I dunno, it's just always been there.
[Caption below the panel:]
If it didn't exist, the moon would sound like such an outlandish sci-fi concept.
{{comic discussion}}

1340: Unique Date

2023-06-08T18:00:31Z

Boochin:

{{comic
| number = 1340
| date = March 10, 2014
| title = Unique Date
| image = unique_date.png
| titletext = If our current civilization lasts another 8,000 years, it's probably fair to assume the Long Now Foundation got things right, and at some point we started listening to them and switched to five-digit years.
}}

==Explanation==
In this comic [[Cueball]] is excited about the current date and he states this date (the date the comic was released) as 2014-03-10, with the year first, then the month, then the day of the month. This follows the international standard as defined in the {{W|ISO 8601}} standard. He then continues to point out, to [[Megan]] and another Cueball, that this date will never happen again.

The {{W|Gregorian calendar}} is the current way to count time in years, months, and days. Since time moves only forward,{{Citation needed}} dates will never repeat. Every date is thus equally unique, even when the digits aren't in a pattern.

Many people do, however, make a big deal about dates when the digits follow an interesting pattern, such as 2000-01-01 or 2012-12-12. They might plan special events on these "unique" days. For instance, [http://articles.latimes.com/2007/jul/08/nation/na-weddings8 2007-07-07] was considered a "lucky" day and had a record number of weddings. This is because humans, in general, are superstitious and like (and recognize) patterns in everyday life, also including patterns in the numbers used for stating dates. But this does not make these dates more unique than any other dates.

Nevertheless, Cueball has made it into [[:Category:My Hobby|his hobby]] to point this daily uniqueness out, and having to listen to him stating this fact every day would be incredibly annoying to his friends.

The title text refers to the {{W|Long Now Foundation}}, which uses [http://blog.longnow.org/02013/12/31/long-now-years-five-digit-dates-and-10k-compliance-at-home/ five-digit years] (e.g. this comic's date would be written "02014-03-10"). This is an effort to encourage people to think in terms of long-term benefits, rather than only the coming years or decades. The {{w|Y2K problem}} was due to using only two digits to store the year, which would have made dates ambiguous when it rolled from 99 back to 00. See also the "{{w|Year 2038 problem}}". Similarly, the {{w|Maya calendar}} had a repeating cycle of 52 years, and even their "long count" rolled over after 7885 years. As we currently use four-digit years this may cause a {{w|Year 10,000 problem|Y10K problem}}.

The Long Now Foundation designs a [http://longnow.org/clock/ 10,000-year clock] that should be able to run for this long — and in principle, it could display every date up to 9999-12-31. 8000 years from the date of the comic would be 10014 AD — [[Randall]] jokes that by switching to 5-digit years, we'd prove the Long Now Foundation correct, although of course by this point there would be no other way to show years except by rebooting the calendar.

A previous comic on date formats was [[1179: ISO 8601]]. Randall addresses date formatting confusion again in the title text of [[1467: Email]].

==Transcript==
:[Cueball speaking to Megan and another Cueball-like guy.]
:Cueball: Whoa, it's 2014-03-10!
:Cueball: Under our system, that date will ''never happen again!!''
:[Caption below the frame:]
:My Hobby: Pointing this out every day.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Multiple Cueballs]]
[[Category:My Hobby]]
[[Category: Calendar]]

Talk:1753: Thumb War

2023-05-26T04:02:24Z

Boochin:

I love this new perspective of the comic. Seeing the characters as kids is an interesting concept, especially when one of them is Black Hat. Hopefully more of these kind of comics will come to exist. I wonder what kind of "classhole" tendencies Black Hat had as a kid... --[[User:JayRulesXKCD|JayRulesXKCD]] ([[User talk:JayRulesXKCD|talk]]) 14:38, 31 October 2016 (UTC)
:We also get to see Black Hat as a child in 1139: Rubber and Glue --[[Special:Contributions/172.68.78.124|172.68.78.124]] 15:00, 31 October 2016 (UTC)
::Well, yes, but I wonder... will Randall do anything else with this? --[[User:JayRulesXKCD|JayRulesXKCD]] ([[User talk:JayRulesXKCD|talk]]) 11:21, 1 November 2016 (UTC)
:::I do not think so. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:18, 1 November 2016 (UTC)

Is this really Hairy in the comic or just a young Cueball, just with hair? Note that also Black Hat has visible hair under his hat in this comic, whereas the adult version doesn't have hair (or at least none visible). [[Special:Contributions/162.158.202.141|162.158.202.141]] 14:48, 31 October 2016 (UTC)
:This is Hairy as Hairy is not a single character, but just the name used to identify a stick figure with hair and to distinguish them from a Cueball (a stick figure without hair). The characters with hats are pretty much the only ones assumed to be non-generic recurring characters. Also, Black Hat does have hair, as seen in comic 377: Journal 2 --[[Special:Contributions/172.68.78.124|172.68.78.124]] 15:03, 31 October 2016 (UTC)
::It can be discussed again and again if children represents the adults. The current explanation makes it clear that these are children that probably grow up to be the two characters. In principle I would say they are not those two, just as any child drawn like Cueball or Megan are not those. And for that same reason it could be argued that this is not Hairy. But if the other is Black Hat as a child then why not Hairy. Both are also in the [[1139: Rubber and Glue]] mentioned above. (Actually all four mentioned here are in that as children). For the sake of this explanation it makes sense to use the names). --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:18, 1 November 2016 (UTC)
:::A good way to get around generic and recurring, diferentiated characters is to follow Black Hat Guy. Since he's one of the two most consistent recurring charaters of them all since [[72: Classhole]] (his literal establishing character moment), you can get the personalities, behavioural traits and relationships of the recurring Cueball, Megan, Hairy, Ponytail, etc. from looking at those that interact with him (you can do that with Beret Guy as well). It's not perfect, but you can establish your own canon regarding "the gang" and their adventures. {{unsigned ip|198.41.230.41}}

I didn't see Hairy's not wanting to play anymore as boredom but as either developing fear, or/and not wanting to play by weird rules he doesn't understand. Trivia; my school yard version didn't have a 5-6-7-8..., our thumb's shook "hands" and bowed to each other before the fight began. ~~[[Cris]] [[Special:Contributions/108.162.245.57|108.162.245.57]] 15:42, 31 October 2016 (UTC)
: Agreed (on both parts). The current description's "…and then counting up by fours and making rhymes" was utterly foreign to me, and I had to read it a few times to make sure it really was implying that it was standard to count above four. I've ''never'' heard of anything beyond "One, two, three, four; I declare a thumb war!" (accompanied by the thumbs touching alternating sides of the "ring"). Unless we can get anyone who can support the claim that counting above 4 (with or without rhymes) is normal or even uncommon, it should probably be expunged. [[Special:Contributions/108.162.215.220|108.162.215.220]] 16:51, 31 October 2016 (UTC)
::I always learned it with two verses, although the second one varied - "1, 2, 3, 4. I declare a Thumb War." and then either "5, 6, 7, 8. Try to keep your thumbs straight." or "5, 6, 7, 8. This'll be a piece of cake." The last word of the second verse was the cue for the fight to begin. --BoomerSooner[[Special:Contributions/162.158.74.42|162.158.74.42]] 17:31, 31 October 2016 (UTC)
:::Same. [[User:NotLock|NotLock]] ([[User talk:NotLock|talk]]) 20:00, 1 November 2016 (UTC)

"Twenty" is a pretty good rhyme for "bunny" if you pronounce it "twenny", which is common in North America. Also, our local variant of Thumb War also stopped at four. [[User:Jkshapiro|Jkshapiro]] ([[User talk:Jkshapiro|talk]]) 01:16, 1 November 2016 (UTC)
:Okay, I thought I was alone, though where I come from it's pronounced [https://commons.wikimedia.org/wiki/File:En-us-twenty.ogg /ˈtwʌn(t)i/]. (And I reveal the smallest bit more information about myself to the internets. Private eyes, gawk away.) --[[User:XndrK|XndrK]] ([[User talk:XndrK|talk]]) 02:48, 1 November 2016 (UTC)

Plot twist: The character on the ''right'' is the one who grows up to be Black Hat. The one on the left is never seen as an adult, because Black Hat takes his hat, resulting in instant regression into emo stuff. [[User:Hppavilion1|Hppavilion1]] ([[User talk:Hppavilion1|talk]]) 04:30, 1 November 2016 (UTC)
:Well funny, but since it's Hairy on the left that is afraid of Black Hat this just doesn't make any sense ;-) --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:18, 1 November 2016 (UTC)

Did other local variants have the index finger "sneak attack"? Index finger sneak attacks were always in play for me... [[Special:Contributions/108.162.238.47|108.162.238.47]] 21:06, 2 November 2016 (UTC)

Is the addition of guessing what Black Hat would say after twenty and twenty-four really necessary? It's just guessing, and does not help explain the comic in any way. [[User:Boochin|Boochin]] ([[User talk:Boochin|talk]]) 04:02, 26 May 2023 (UTC)

1036: Reviews

2023-05-26T03:29:07Z

Boochin:

{{comic
| number = 1036
| date = March 30, 2012
| title = Reviews
| image = reviews.png
| titletext = I plugged in this lamp and my dog went rigid, spoke a sentence of perfect Akkadian, and then was hurled sideways through the picture window. Even worse, it's one of those lamps where the switch is on the cord.
}}

==Explanation==
[[Cueball]] and [[Megan]] are shown shopping for lamps. In the first frame of the comic, it is at a time before online reviews could be looked up on a smartphone. They spot a lamp they like, check the price, and agree to buy, end of story.

But the rest of the comic shows how difficult shopping has become after reviews have become easily accessible on smartphones while standing in the store. And now this takes up the final three panels, with the result that no lamps have been acquired and they decide to sit in the dark, using the claim that their living ''room looks fine in the dark'' to avoid buying a very expensive lamp which is the only one with perfect reviews (like 100% with 5 stars out of 5).

When shopping for anything via {{w|reviews}}, whether it be electronics or even something as simple as lamps like the comic demonstrates, one negative review can spoil a lot of positive reviews. That hits home even more if the review is specific because humans attach more weight to anecdotes and specific stories. This comic points out the absurdity of paying attention to those reviews, by making the negative review itself absurd (a lamp making your cats go deaf and interfering with your taste buds would imply, at the very least, anomalous radiation, and would not be on store shelves long before some kind of serious recall).

The second part of the comic starts out normal. For the lamp Cueball think is pretty Megan finds ''lots'' of negative reviews which implies the product really isn't good after all, and it was even that specific brand of lamps in general that was to be avoided. But then this proceeds to get more and more absurd all the way to the title text. Cueball is for instance looking at a lamp that someone thinks looks like a {{w|uterus}}. As normal people do not really know what a uterus looks like, and if Cueball did not find this so himself, he should ignore one person's comment. On the other hand, reading such a statement will maybe make you think of a uterus every time you see the lamp. So now it may be best not to buy it, but had he not read the comment it might have been a fine lamp for him.

In the final frame Cueball has found a Swiss lampmaker with perfect reviews, but her lamps are very expensive, the cheapest are starting at 1,300 francs. {{w|Swiss franc|Swiss francs}} are the units of currency used in {{w|Switzerland}}. In 2012 when the comic was released a Swiss franc was worth a little more than one dollar ([http://www.exchangerates.org.uk/CHF-USD-30_03_2012-exchange-rate-history.html 1.1$ to a Swiss Franc]) making the cheapest lamp go for not much less than US$1450. For comparison, US$15 can get a decent lamp at IKEA. Furthermore, the lampmaker lives in the {{w|Swiss Alps}} and can only be reached via a {{w|ski lift}}. This either indicates that transportation will be very expensive on top of the high starting price or it may even indicate that they will have to go to the lampmaker personally to either acquire a lamp or maybe just to check out that they really do not look like a uterus or [http://gizmodo.com/5360742/penis-chandelieryes-penis-chandelier other parts] of the human reproductive system...

The title text is presumably the review of another lamp. When this reviewer plugged in this lamp, supposedly his dog went rigid, delivered a line of perfect Akkadian, and then was hurled sideways out the picture window. {{w|Akkadian_language|Akkadian}} is an extinct {{w|Semitic language}} that was spoken in {{w|ancient Mesopotamia}}. Even if the dog actually did speak a sentence of perfect Akkadian, the chance that the owner would be able to recognize it as such is negligible. The final joke is that the worst part of this lamp, was not the above mentioned crazy effects on the dog, but that the lamp had, completely normally, the switch on the cord, as opposed to having it on the body of the lamp. A production argument about where to place such a switch, leading to someone getting fired, was part of the joke in [[1741: Work]].

==Transcript==
:[Cueball and Megan stand in a store looking at a lamp that Cueball points at on a table in front of them. There is another table behind them with another lamp and next to it stands a box with a picture of yet a different type of lamp in the bottom right corner. Both lamps have a price tag dangling from their shade. Above them (and their spoken text) is a frame with a caption:]
:Shopping before online reviews:
:Cueball: This lamp is pretty.
:Megan: And affordable.
:Cueball: Let's get it.
:Megan OK!

:[Exactly the same setting as above except now Megan holds up her smartphone in one hand looking down at it while typing on it with the other hand. Above them (and their spoken text) is a frame with a caption:]
:Shopping now:
:Cueball: This lamp is pretty.
:Megan: It's got 1½ stars on Amazon. Reviews all say to avoid that brand.

:[To the left of Cueball there is another lamp on a table. But he is now looking at his smartphone instead. Megan has turned away from him but is also looking at her smartphones. There are no lamps next to her.]
:Cueball: This one has good reviews.
:Megan: Wait, one guy says when he plugged it in, he got a metallic taste in his mouth and his cats went deaf.
:Cueball: Eek.
:Cueball: What about- ...no, reviews points out it resembles a uterus.

:[Cueball is holding his smartphone up in front of his face, Megan, looking at him, is holding her smartphone but has her arms down. There are no lamps shown.]
:Cueball: OK, I found a Swiss lampmaker with perfect reviews. Her lamps start at 1,300 Francs and she's only reachable by ski lift.
:Megan: You know, our room looks fine in the dark.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Smartphones]]
[[Category:Animals]]
[[Category:Online reviews]]

1853: Once Per Day

2023-05-25T15:51:19Z

Boochin:

{{comic
| number = 1853
| date = June 21, 2017
| title = Once Per Day
| image = once_per_day.png
| titletext = I'm not totally locked into my routine—twice a year, I take a break to change the batteries in my smoke detectors.
}}

==Explanation==
Many news reports on health recommend the "best" way to perform the processes, such as eating, drinking, exercising, or sleeping, that are required to live healthy. These reports tend to give such factors as a type of food to consume regularly, the amount of a nutrient to consume, or how long to exercise, in terms of what or how much to do daily. A simple example of this is the proverb, "An apple a day keeps the doctor away." Perhaps this kind of advice is [[1592|overthinking]] things, but [[Cueball]] decides to follow it strictly as explained in the caption.

So when [[Megan]] asks Cueball what his plans are, he just lists his routine consisting only of things that the news has told him exactly how often to do.

His list includes the following, which he has to do once per day:
*Eat an [//www.care2.com/greenliving/10-reasons-to-eat-an-apple-a-day.html apple] - This references the common old wives tale of "an apple a day keeps the doctor away"
*Eat an [//www.nhs.uk/news/2016/11November/Pages/Eating-one-egg-a-day-may-lower-risk-of-stroke.aspx egg] - One egg would provide protein. This could also be a stand in for "breakfast is the most important meal of the day"
*Take one [//www.webmd.com/men/features/aspirin-day-not aspirin] - {{w|Aspirin}} can reduce heart issues. Baby aspirin would contain a lower dose and be safe.
*Eat a piece of [//www.everydayhealth.com/diet-and-nutrition-pictures/delicious-reasons-to-eat-dark-chocolate.aspx dark chocolate] (see also {{w|John_Bohannon#Misleading_chocolate_study|John Bohannon's chocolate study}} for an example of how bad science can wind up as such "you should do ... daily" suggestions in the media) - Dark chocolate would contain more antioxidants and less sugar.
*Drink [//www.lifescript.com/diet-fitness/tips/y/your_weight-loss_solution_drink_6_glasses_of_water_a_day.aspx six glasses of water] - There is a common, long standing myth that you're supposed to [[1708:_Dehydration|drink X amount of water per day]]. Some say 6 or 8 cups. A liter or two. etc. etc.
*Drink [//www.health.com/health/article/0,,20410287,00.html one glass of red wine] - Always used as a "health can be fun" example. Wine would contain large amounts of antioxidants, and one glass a day shouldn't cause liver damage.
*Drink [//www.huffingtonpost.com/2013/10/17/coffee-health-benefits_n_4102133.html a cup of coffee] - Coffee is one of those health items that has a new health benefit or loss every week, depending on which media outlet you follow.
*Drink [http://www.huffingtonpost.com/2014/12/11/reasons-to-drink-tea_n_6276862.html a cup of tea] - Tea's health benefits are a very common subject. There is much media talk about the benefits of different types of teas, usually focused around Green Tea.
*Get [http://www.webmd.com/fitness-exercise/news/20120824/30-minutes-daily-exercise-shed-pounds 30 minutes of exercise] - Different media outlets give different amounts of exercise to do. Usually, they tend towards 15-30 minutes a day to sound easy and low commitment.
*Get [http://archive.jsonline.com/news/health/studies-say-7-8-hours-of-sleep-is-needed-for-best-health-b9936714z1-212691521.html/ 8 hours of sleep] - An average adult needs 6-8 hours of sleep daily, but this varies per person, and by age.

Several obvious problems arise with these "you should do ... daily" tips. They are often based on population studies, but they may be harmful in the case of some individual persons. This health-related advice would be beneficial in, say, 60 or 70% of the population, but may be ineffective in other 20% of the people, and deleterious in 10%. This especially relates to the suggested daily intake of aspirin.

The second problem is the shaky scientific foundation of this advice. There have been studies examining the effects of a daily glass of red wine, for example, but there is certainly no study which has observed the ''interaction'' of all ten of these health tips at once. In particular, {{w|tannin}}s (which occur in red wine and coffee) are known to absorb certain substances, which may influence the way in which apples and eggs are digested.

Furthermore the scientific basis for these articles are shaky at best. A large number of these studies are just junk science - poor methodology and bias making the study more attention-grabbing, but lacking real substance. Even those studies that are scientifically rigorous are often reported on poorly. "Study proves that dark chocolate helps you lose weight" is a better headline than "Several studies over the last five years hint that chocolate may have certain long term benefits; more research needed"

Of course, if Cueball ''only'' does these things, then he can't/doesn't attend to other important matters, such as going to work, which most likely allows him to buy the recommended materials in the first place, or even using the toilet. Also, if Cueball only does these things, he will complete his "daily" schedule in significantly less than a day, probably between 8.5 and 9 hours. This means that he will do his "daily" schedule on average almost three times a day. One consequence is that Cueball will be drinking on average about 19 glasses of wine per week instead of 7 glasses of wine per week if he actually drank one glass of wine per day. While drinking 7 glasses of wine per week won't have any negative consequences as long as they are evenly or about evenly spaced, drinking more than fourteen servings of alcohol (where one glass of wine has one serving of alcohol) per week causes long-term liver damage. Also, it's not clear how Cueball is able to overpower his circadian rhythm in order to sleep for over twenty hours per day. Furthermore, while the routine is theoretically subject to change as soon as Cueball hears another such daily recommendation on the news, this won't happen because he hasn't heard a recommendation to tune in to the news every day, so poor Cueball is trapped in his daily schedule.

In the title text Cueball explains that his daily routine is not completely fixed. It is broken twice a year, since he also follows public information campaigns suggesting the replacement {{w|Smoke_detector#Batteries|smoke detector batteries}} twice a year. While the US {{w|National Fire Protection Association}} recommends a replacement at least once per year others suggest every time when the clock changes according to {{w|daylight saving time}}, i.e. twice a year. (All such recommendations will likely become irrelevant as citizens of the United States, starting in California, are encouraged to replace their existing smoke detectors with new models containing irremovable ten-year batteries.) This is just another example for official overdone recommendations nobody follows, in this case since smoke detectors make annoying beeps when their batteries run low and thus rarely need routine replacements before then.

==Transcript==
:[Megan and Cueball are standing together, facing each other.]
:Megan: Got any plans for the day?
:Cueball: I'm going to eat an apple, an egg, one baby aspirin, and a piece of dark chocolate, drink six glasses of water, one glass of red wine, a cup of coffee, and a cup of tea, then do 30 minutes of exercise.
:Cueball: Then back to sleep for another 8 hours!

:[Caption below the panel:]
:I only do things that news stories have specifically told me to do once per day.

==Trivia==
*Fire alarms were also the subject at [[1794: Fire]].
*Drinking six glasses of water per day has been the subject in [[1708: Dehydration]], and earlier, when it was more common to say eight glasses per day, in [[715: Numbers]].
*If Cueball actually did all these things once per day, then he would have to stretch out the eating and drinking over 15 hours and 30 minutes.

{{comic discussion}}

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

1644: Stargazing

2023-05-24T15:51:09Z

Boochin:

{{comic
| number = 1644
| date = February 17, 2016
| title = Stargazing
| image = stargazing.png
| titletext = Some of you may be thinking, 'But wait, isn't the brightest star in our sky the Sun?' I think that's a great question and you should totally ask it. On the infinite tree of possible conversations spread out before us, I think that's definitely the most promising branch.
}}

==Explanation==
This is the first comic in the [[:Category:Stargazing|Stargazing]] series. It was followed by [[2017: Stargazing 2]] two and a half years later and [[2274: Stargazing 3]] four years later.

This comic opens on [[Megan]] as the host for a {{w|stargazing}} TV show, or simply a stargazing tour. She claims to be a doctor, although it is unclear what exactly she's a doctor in. Her remarks, however, may call her professionalism into question. (Originally the host was suspected to be a spoof on {{w|Brian Cox (physicist)|Brian Cox}}, see [[#Relevant TV-shows|below]], but at some later point [[Randall]] changed his official transcript thus making the host female rather than male as in the original version, see the [[#Trivia|trivia]] section below. Thus now the host is clearly Megan, which it could not have been originally when the host was described as a man by Randall).

Throughout the comic the host's tone and choice of words becomes increasingly unprofessional, referring to most of the stars as "shitty," personifying them based on different astronomical observations, and providing little useful information on the study of stars or how they work.

It seems that this is not an isolated issue as the television host mentions that people keep asking her whether or not she is a real astronomer.

The host also continuously glosses over the arguably less exciting portions of a typical presentation on astronomy sharing only what she sees as "the good stuff." This penchant for only caring about something if it is interesting extends past astronomy as well as the host is too bored when reading the dictionary to look up the meaning of astronomer.

The comic derives much of its humor from the absurdity of the host's comments on various astronomical bodies. Although not technically incorrect, the way she presents the information is far from informative. (See details below on [[#The host's observations|the host's observations]]).

One of her observations regards the fact that {{w|Sirius}} is a {{w|binary star}}, a system where two stars orbit each other. So even though it is the brightest star as seen from Earth we only really see one of them, as the other is, to quote the host, "not even trying". Sirius A is "large" and "bright" {{w|main sequence}} white star, while Sirius B is a {{w|white dwarf}} with a little under half the mass, 0.49% the radius and only 0.22% the luminosity of Sirius A.

{{w|Andromeda Galaxy|Andromeda}} is the largest galaxy in our {{w|Local Group}}. It is 220,000 light years across and contains a trillion stars. Humans have difficulty conceptualizing distances of this scale. Suffice to say that it is very large.{{Citation needed}}

{{w|Betelgeuse}} is the 9th brightest star visible from earth. One of its prominent features is its visible redness. Within the next million years (or maybe only 100,000 years) it is expected to explode as a {{w|supernova}}, which will certainly be a spectacular sight. It could happen anytime now, and the host hopes it will be in her lifetime.

In the title text it is mentioned that the {{w|Sun}} is also a star and of course is much brighter than Sirius seen from Earth, and thus Sirius is technically not the brightest star in our sky (although it is in the night sky). The title text sarcastically encourages the audience to raise that obvious but irrelevant point (a standard joke when people mention bright stars) instead of asking a more interesting, informative, or fruitful question, when there are so many to ask regarding astronomy.

See also [[1371: Brightness]] and [[1342: Ancient Stars]]. Saying cool things about space to make people like you is mentioned in [[1746: Making Friends]].

===The host's observations===
Here is a list of the host's observations:
*Most {{w|Bright Star Catalogue|visible stars}} are still very faint, and just become background to the bright {{w|stars}} that form the named {{w|constellations}}.
**The host correctly states that they are just dots. (This is also true for the bright stars, but at least they are clearly distinguishable).
*{{w|Sirius}} is the {{w|Apparent magnitude|brightest}} star in our {{w|List of brightest stars|night sky}}. But it is not the brightest object in the night sky, as several of the planets, especially {{w|Venus}} and {{w|Jupiter}}, and of course the {{w|Moon}} are much brighter. It is also far from being one of the most {{w|Absolute magnitude|luminous stars}} in the {{w|Milky Way}}, but its proximity to Earth makes it the brightest in the night sky. There are {{w|List_of_most_luminous_stars#Data|twenty visible stars}} that are more luminous than Sirius, {{w|List of most luminous stars|none of which}} come even close to being in the top 100 of the most luminous stars observed today.
**The host thus names Sirius as the star in charge since it outshines all the others as seen from the {{w|Earth}}.
*Sirius is actually a star system consisting of two stars as it is a {{w|binary star}} system. But where Sirius A is twice the size of the {{w|Sun}} and much brighter, then Sirius B is now just a dim {{w|white dwarf}}, the remains from a much larger star that became a {{w|red giant}} before shedding its outer layers and collapsing into its current state around 120 million years ago. So now Sirius A completely outshines Sirius B, which actually is now a dead star with no further fusion going on inside its core.
**This is construed by the host as it is barely even trying, as it is now only radiating away the rest of the heat from the now exposed core.
*{{w|Andromeda Galaxy|Andromeda}} is a {{w|spiral galaxy}}, like the Milky Way, and it is the largest galaxy in the {{w|Local Group}} where our own galaxy the Milky Way is the second largest. It is one of a few visible objects that are located outside the Milky Way. It is "only" 2.5 million light-years from the Sun and it is heading our way (or vice versa), and will {{w|Andromeda–Milky Way collision|collide with the Milky way}} in about 4 billion years (before the Sun goes into {{w|Sun#After_core_hydrogen_exhaustion|its red giant phase}}). Being 220,000 light years across and consisting of a trillion stars, it is somewhere between 1.2-2.2 times wider than the Milky Way and has 2.5-10 times as many stars. (The local group was also mentioned two comics ago, in [[1642: Gravitational Waves]], together with the much less well known third largest galaxy in the group the {{w|Triangulum Galaxy}}).
**It is therefore true when the host says that it is too big to try to understand, and thinking about it will make your head spin, so she suggests we do not think about it.
*{{w|Betelgeuse}} is a clearly visible (9th brightest) {{w|Red_supergiant|red supergiant}} {{w|Semiregular_variable_star|variable star}} located in the {{w|Orion (constellation)|constellation of Orion}}. It is one of the largest and most luminous observable stars (12th) and one of the few where it is clear that the light is not white. Most people can see that it is slightly red, whereas most other stars are so faint that they look white despite having different colors (when seeing Orion's two brightest stars, to remember which is which between Rigel and Betelgeuse, its diagonal opposite, just remember: Rigel is "R" like blue, and Betelgeuse is "B" like red). It is expected that Betelgeuse, being at a late stage of its {{w|Stellar_evolution|evolution}}, {{w|Betelgeuse#Approaching_supernova|will go supernova}} within the next million years as a {{w|type II supernova}}. The exact time when it will become a {{w|Supernova}} is so uncertain that it could [http://earthsky.org/brightest-stars/betelgeuse-will-explode-someday#explode just as likely happen tomorrow] as in a million years. When it happens it will not be dangerous to anyone on Earth, but it will likely be visible even during the day, as it may even become as bright as the full Moon.
**When it does go nova, it will be a fantastic spectacle for everyone, but especially for anyone who likes the ''good stuff'' in space like the host, who cannot wait for the star to explode. Clearly she hopes it will be in her lifetime, and, although this is unlikely, there is a small chance that it might just happen.
*A {{w|meteor}} (also known as {{w|shooting star}}), is debris from space that rains down on Earth, and burns up in the atmosphere. This happens all the time, but you need to be either lucky, patient, or know the right time for one of the {{w|meteor showers}} to see one. Often they are visible for so short a time period, that it is difficult to share the experience with anyone, as it will be gone by the time they turn their head to look where you are pointing.
**The host becomes very excited when she spots such a meteor, especially because it is likely that her audience got to share the experience with her, as they were already looking in the same direction as her. But still she asks if they saw it, because it is so short lived.
*{{w|Outer space}} is the void that exists between {{w|Astronomical object|celestial bodies}}, including the Earth. There is by definition nothing there but {{w|vacuum}}, and the interesting part of space is thus not the space but the astronomical objects found out there.
**The host says that ''space is cool'', which is a very un-astronomical comment, as explained above. Also her excitement for a simple shooting star is cause for the suspicion that is raised after her space comment.

===Relevant TV-shows===
The comic could be a reference to BBC's ''{{w|Stargazing Live}}'', which {{w|Brian Cox (physicist)|Brian Cox}} has appeared in since 2011. If drawn in xkcd style he would likely look like Megan. He has a PhD in high-energy {{w|particle physics}}, but not astronomy. The newest season of the show aired during January 2016 just a month before this comic's release. Brian Cox has also been the presenter of several other science programs, especially such as the ''{{w|Wonders of the Solar System}}'', ''{{w|Wonders of the Universe}}'' and ''{{w|Wonders of Life (TV series)|Wonders of Life}}''. Originally the host was described as male in the official transcript (see [[#Trivia|trivia]] below, making this seem more likely. for some reason Randall changed the host to female in the transcript later. Very strange, but for sure when he was male, it was obviously a Brian Cox spoof.

It could also be a reference to {{w|Jack Horkheimer}}'s PBS shows ''Star Hustler'' and ''{{w|Star Gazers}}''. Horkheimer, however, does not at all look like Megan, and he died 6 years ago. But he was not a doctor in astronomy, only getting into it when he started volunteering at the Miami Museum of Science's planetarium. He ended up writing shows for the planetarium and the PBS series developed from there. He rarely covered facts about the night sky that couldn't be found in any basic reference (possibly because the show was aimed at children and non-astronomy buffs), although he did get more in-depth about current astronomical events such as {{W|Comet Hale–Bopp}}.

==Transcript==
:[A thin panel with Megan as a TV-host is holding her hands up. She is drawn in white on a black background. Behind her is an audience drawn in faint gray lines consisting of Hairy (to the left) and two Cueball-like guys and Ponytail (seen in a rare full face position) to the right of the host. One of the Cueball-like guys is partly hidden behind the host.]
:Host: Welcome to stargazing, with your host, me.
:Host: I'm a doctor or whatever.

:[Same scene as before but in a broader panel, and the host is now holding only one hand up with a finger pointing up. The audience is the same four people, but now Hairy has moved further to the left in the panel to make room for a Megan-like woman also to the left of the host.]
:Host: I'm not gonna waste your time on the shitty stars.
:Host: Just the good stuff.
:Host: Honestly half of 'em just look like dots.

:[A frame-less drawing with a zoom out showing the group of six people in black silhouette on a white background. Part of the ground beneath them is shown as a black pool. The host is pointing up with one hand. The people have been rearranged, so left of the host is now a Cueball-like guy and a Megan-like woman, and to the right is the other Cueball-like guy, then Ponytail (seen from the side as usual) and Hairy. All are looking up following the host's directions.]
:Host: This is Sirius. It's the brightest star in our sky so it's in charge.
:Host: It's really two stars but one of them is barely even trying.
:Host: This is Andromeda, it's too big to think about, so let's not.

:[Zoom in of the host's upper body, again drawn in white on a black background. She is looking right gesturing with one arm raised, and the other still pointing up with a finger stretched out. Her audience is no longer shown.]
:Host: That red stars is Betelgeuse. It's gonna explode someday.
:Host: Can't happen soon enough, as far as I'm concerned. I-
:Host: ''Holy shit did you see that meteor!?!''
:Host: Space is ''awesome!''

:[Same scene as the previous panel, but the host has turned towards left looking at someone in the audience (not shown) who speaks off-screen. She has taken both her hands down for the first time.]
:Off-screen voice: Are you ''sure'' you're an astronomer?
:Host: People keep asking that, so I finally tried to look that word up in a dictionary, and ''wow'' is that book ever boring. No thank you.
:Off-screen voice: But-
:Host: ''Space!''

==Trivia==
*Randall changed the [http://www.explainxkcd.com/wiki/images/archive/4/48/20160221022727!stargazing.png original] posted version of the comic.
**The only thing that changed was in the third panel where '''''That's''' Andromeda'' was changed to the current version: '''''This is''' Andromeda''
*The official transcript [https://web.archive.org/web/20160913162302/http://xkcd.com/1646/info.0.json originally] used male pronouns for the TV host. It now (as of 2019) uses female pronouns for the host.
**The official transcripts seems to have been messed up on xkcd at the time being.
***The [http://xkcd.com/1644/info.0.json transcript for 1644] is thus at the moment a mix of that comics main info (top and bottom) which results in the correct title and title text, but the entire description in this transcript is describing the comic from two releases before no. [[1642]].
***This seems to be a general problem for comics released around that time...
***Thus the description of this comic, was first released when comic no. [[1646]] came out.
***This has not been corrected (4 years later at the time of writing)!
****So the official transcript for 1644 can be found [http://xkcd.com/1646/info.0.json here], together with the data for comic 1646.
**The current transcript is included here below:
::(Inverse color panel - white on black)
::[A television host in the foreground, speaking toward the reader. A group of other people are in the background behind them.]
::Host: Welcome to Stargazing, with your host, me. I'm a doctor or whatever.
::[She continues to talk.]
::Host: I'm not gonna waste your time on the shitty stars. Just the good stuff. Honestly half of 'em just look like dots.
::(Normal color panel - black on white)
::[A shot from far away of the host standing in the center of the group of people watching her, she points to the sky.]
::Host: This is Sirius. It's the brightest star in our sky so it's in charge. It's really two stars, but one of them is barely even trying. This is Andromeda. It's too big to think about, so let's not.
::(Inverse color panel)
::[Close-up on the host gesturing toward the sky behind her.]
::Host: That red star is Betelgeuse. It's gonna explode someday. Can't happen soon enough, as far as I'm concerned. I--
::HOLY SHIT DID YOU SEE THAT METEOR?!?!
::Space is awesome!
::[The host speaks to someone out of panel.]
::Other: Are you sure you're an astronomer?
::Host: People keep asking that, so I finally tried to look that word up in a dictionary, and wow is that book ever boring. No thank you.
::Other: But--
::Host: SPACE!
:*The original official transcript with male host is included here below (correcting a typo with a missing "s" in "stuff" and formatting to look like our normal transcripts):
::[A television host in the foreground, speaking toward the reader. A group of other people are in the background behind them.]
::Host: Welcome to Stargazing, with your host, me. I'm a doctor or whatever.
::[He continues to talk.]
::Host: I'm not gonna waste your time on the shitty stars. Just the good stuff. Honestly half of 'em just look like dots.
::[Normal color panel - black on white. A shot from far away of the host standing in the center of the group of people watching him, he points to the sky.]
::Host: This is Sirius. It's the brightest star in our sky so it's in charge. It's really two stars, but one of them is barely even trying. This is Andromeda. It's too big to think about, so let's not.
::[Inverse color panel. Close-up on the host gesturing toward the sky behind him.]
::Host: That red star is Betelgeuse. It's gonna explode someday. Can't happen soon enough, as far as I'm concerned. I-- ''HOLY SHIT DID YOU SEE THAT METEOR?!?!'' Space is ''awesome''!
::[The host speaks to someone out of panel.]
::Other: Are you ''sure'' you're an astronomer?
::Host: People keep asking that, so I finally tried to look that word up in a dictionary, and ''wow'' is that book ever boring. No ''thank'' you.
::Other: But--
::Host: ''SPACE!''

{{comic discussion}}

[[Category:Stargazing]]
[[Category:Comics sharing name|Stargazing]]
[[Category:Comics with inverted brightness]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Hairy]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Multiple Cueballs]]
[[Category:Astronomy]]
[[Category:Space]]

2540: TTSLTSWBD

2023-05-18T15:34:36Z

Boochin:

{{comic
| number = 2540
| date = November 10, 2021
| title = TTSLTSWBD
| image = ttsltswbd.png
| titletext = Tomorrow's sessions will be entirely devoted to sewing machine rotary hooks.
}}

==Explanation==

[[Cueball]] is standing at a lectern on a [[1661: Podium|podium]], addressing a large crowd. He is describing the program of some event, listing the different topics that will be covered. These appear to be random, but the caption gives the punchline: it is a conference on things that seem like they shouldn't work but do.

By "things that seem like they shouldn't work", it means things that the average person would have some intuitive sense that the function of thing was impossible, and yet ample real-world experience shows that they do, and may become a routine function that people depend upon. TTSLTSWBD in the title and the banner is the abbreviation for "Things That Seem Like They Shouldn't Work, But Do".

{{w|Organ transplantation}}, where a functioning organ is cut out of one person (possibly a dead one) and put into another person where it will now operate for their benefit. Given the very complex and delicate nature of living tissue, it's rather surprising that this could work at all. In reality, it's not a simple process, and a lot of things could go wrong, but modern medicine is advanced enough that organ transplantation is widely accepted and regularly practiced, usually functioning well enough to extend life.

{{w|Airship|Airships}}, or dirigibles, are [https://upload.wikimedia.org/wikipedia/commons/e/ee/Giant_Aircraft_Comparison.svg huge], rigid structures which are filled with bags of lighter-than-air gas, which causes the entire structure to float, and could carry both passengers and significant loads. The idea of such a huge vessel traveling, able to both move rapidly and float in place, would be hard to imagine if it didn't exist, yet zeppelins functioned and were a practical mode of transportation for a time. Unlike the other things mentioned, airships are largely obsolete (having lost favor due to {{w|Hindenburg_disaster|safety concerns}} and surpassed by other technologies). Airships are a [[:Category:Airships|recurring theme]] on xkcd.

{{w|Lunch|Lunch}} is listed as if it was another topic of the TTSLTSWBD, but it probably just means that after discussing airships, the conference will take a break to eat lunch, as many [[1530:_Keyboard_Mash|humans]] usually do.{{Citation needed}}

Mechanical {{w|gyroscope}}s are simple devices consisting of a spinning disc mounted inside three concentric {{w|gimbal}}s as a fixture, or more often observed at work as a single spindle in a free-standing external frame that can be held or moved around by hand. The rotational inertia of the spinning disc resists change in orientation, and tends to remain in a single orientation (if free to do so) or else exert counter-intuitive forces (where directly encouraged to change its central axis). The notion that a disc can remain so steady can be counterintuitive even to those who understand the physical principles. This weirdness has been previously referenced in [[332: Gyroscopes]]. An {{w|Ring laser gyroscope|optical gyroscope}} does not mechanically resist any motion but (relying upon {{w|Sagnac effect|an effect}} originally exploited in a failed attempt to disprove {{w|Special Relativity}}) ultimately provides similar feedback about the rotation of the unit into which it is mounted.

{{w|Butterfly|Butterflies}} fly with an unusual fluttering pattern, which works in part due to the {{w|Ornithopter#Aerodynamics|notoriously complex principles of fluid dynamics}} that may look like uncontrolled fluttering but yet somehow allows the creature to land directly on specific flowerheads to feed. This is not as intuitively understandable as the flight of larger creatures such as birds.

The title text refers to {{w|Rotary hook|rotary hooks}} on sewing machines, which are a complicated (and complicated looking) mechanism whose purpose is to feed one thread in a loop around a whole spool of another thread, and are apparently counterintuitive enough that the conference feels they need a whole day to cover them.

This concept is referenced in [[2115: Plutonium]].

The conference that the comic pictures is another example of a thing that seems like it shouldn't work but does. At first glance, Cueball seems to be listing a random, disconnected list of topics that will be covered, which runs counter to the format of most conferences. It initially seems inconceivable that enough people would be interested in all of those separate topics for the conference to make a profit (from attendance fees). However, the audience is packed, demonstrating that this is not the case. This may be because many people enjoy the mind-expanding feeling of having their intuitions shattered.

==Transcript==
:[Cueball stands behind a lectern on a podium, gesturing with one hand held out, speaking to an audience. A banner hangs on the wall over the crowd with large letters on it. Illegible smaller text is written under these letters.]
:Cueball: Next we have a session on organ transplants and another on airships.
:Cueball: Then lunch, then we'll have one on gyroscopes and one on butterflies.
:Banner: TTSLTSWBD

:[Caption below panel:]
:The first annual conference on Things That Seem Like They Shouldn't Work But Do

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Public speaking]]
[[Category:Animals]]
[[Category:Airships]]