explain xkcd - User contributions [en]

1473: Location Sharing

2022-05-26T19:45:22Z

Green: Undoing vandalism

{{comic
| number = 1473
| date = January 14, 2015
| title = Location Sharing
| image = location_sharing.png
| titletext = Our phones must have great angular momentum sensors because the compasses really suck.
}}

==Explanation==
In this comic, [[Megan]] is visiting a website on her mobile phone. After loading it, the website {{w|Location-based service|asks for her location}}. The choice between allowing or denying a website or app access to certain information is common among smartphones. The term "location sharing" specifically refers to when a smartphone user shares their location with such an entity. An example is a weather app which would need your location in order to automatically find the correct forecast.

Megan is then asked her {{w|momentum}}, which she denies. The joke is based on the Heisenberg {{w|uncertainty principle}}, which, in quantum mechanics, states that some pairs of values cannot be known precisely and simultaneously. The most famous examples of such values, especially in jokes, are location and momentum.

The ramifications of the uncertainty principle being violated in this context are unknown, but the comic might be alluding to security problems that appear if an untrusted application is given access to momentum data generated by the gyroscope. Access to gyroscope data can be used for reading passwords entered into the on-screen keyboard or even guessing keyboard strokes on a keyboard lying on the same table as the phone.

It could also be an attempt to get [[Megan]] to unknowingly reveal her weight (mass to be more exact), as the mass can be inferred by dividing the momentum by velocity (the velocity in turn can be obtained by observing the change of the location over time). In order to be feasible, the location must be polled at least twice, as at least two location points are necessary to compute the velocity. It is a stereotype in many Western cultures that women tend to keep their weight secret. The stereotype implies that women tend to obsess about controlling (and not revealing) their weight in order to conform to societal and sexual pressure.

On the other hand, it could just be a joke about the fact that Heisenberg's uncertainty principle is typically observed only at sub-atomic scales, and not at macroscopic scales (it is possible to measure both the position and momentum of a large object). By saying "Nice try", it's clear that [[Megan]] knows about the principle, but funny that she would think it applies to herself at macroscopic scale.

The title text refers to the inclusion of {{w|gyroscope}}s in modern cell phones that measure angular momentum, mostly to detect when the phone is tilted, but also used in a few mobile games. Randall suggests the poor accuracy of the compasses in mobile phones (measuring the angular position) is due to the gyroscopes being too good. If both the gyroscope and the compasses were completely accurate to a subatomic scale, it would violate the uncertainty principle. Modern phones also include varied technologies (such as GPS) to pinpoint the user's location, with varying degrees of accuracy.

The uncertainty principle has previously been referenced in [[824: Guest Week: Bill Amend (FoxTrot)]]. It has also been discussed in relation to the two comics [[1404: Quantum Vacuum Virtual Plasma]] and [[1416: Pixels]].

==Transcript==
:[Megan is holding her phone. Above her is the text she can see on the screen:]
:This website wants to know your location.
:[Two buttons are below this text. The first is white with a black frame and black text. The second (the chosen button) also has a black frame, but inside the frame is a black rectangle with white text. Around the chosen button are small lines indication rays.]
:Deny
:'''Allow'''

:[Megan is holding her phone.]

:[Megan is holding her phone. Above her is again the text she can see on the screen.]
:This website wants to know your momentum.
:[Two buttons are below this text. The first (the chosen button) has a black frame, but inside the frame is a black rectangle with white text. The second is white with a black frame and black text. Around the chosen button are small lines indication rays.]
:'''Deny'''
:Allow

:Megan: Nice try.

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Physics]]
[[Category:Smartphones]]

1472: Geography

2022-05-26T19:44:59Z

Green: Undoing vandalism

{{comic
| number = 1472
| date = January 12, 2015
| title = Geography
| image = geography.png
| titletext = The place I'd least like to live is the farm in the background of those diagrams showing how tornadoes form.
}}

==Explanation==
The comic is a map showing examples of {{w|geographical feature}}s as they would be presented in a {{w|geography}} textbook. May be based on the first page of the book [http://nicksharratt.com/books/other_authors/you_choose.html You Choose] which displays a map of locations similar in style to the one used in the comic and asks the reader "If you could go anywhere, where would you go?".

[[Randall]] notes that he would like to live in the middle of this region. These maps include an unusual density of different land forms, leading to an interesting environment in which to live. In the real world, these geographical features might take up far more space, and the geologic forces that shape them might create far different patterns than those shown. This kind of {{w|Neverland}} of geographical feature would offer a range of outdoor activities and landscapes that would make it a very nice place to live, as long as the volcano does not erupt.

Some of the geographic features do have a (very) loose similarity to the area around {{w|Boston}}, where Randall lives. Also near Boston is one geographical feature that Randall has included in this map but has refrained from labeling, the {{w|isthmus}} between the peninsula and the forest.

On the other hand, the map actually looks quite a bit like the area around southwestern {{w|Washington (State)|Washington}} and northwestern {{w|Oregon}}, with the reader facing south so the {{w|High Desert (Oregon)|high desert}} is on the upper left. The volcano could be {{w|Mount Rainier|Rainier}} or {{w|Mount St. Helens|St. Helens}}. Real-world outdoor enthusiasts do indeed appreciate the Neverlandish landscape. Having little Spanish influence, locals would refer to a "mesa" as a {{w|butte}}.

The title text discusses a different type of diagram usually found in geography textbooks, the one [http://scied.ucar.edu/sites/default/files/images/large_image_for_image_content/tornado_fmn_lg_0.gif showing the mechanism of tornado formation]. Randall notes that he would least like to live in the farm typically depicted in the background of such diagrams. This is likely because the farm is depicted as being on a vast, featureless stretch of flat prairie, the opposite of the rich landscape in the comic. The monotonous landscape would reflect that of {{w|Tornado Alley}}, an area of the central United States where a large number of tornadoes form, and which makes up a large portion of the {{w|Great Plains}}. His dislike for this type of area may also simply be due to the damage created when a tornado hits. That said, chances of a ''direct'' tornado hit on any given house are slim compared to simply the risk of property damage. Living near an active volcano may be much more dangerous than living in Tornado Alley. Tornadoes are a [[:Category:Tornadoes|recurring subject]] on xkcd.

Here is an alphabetical list of the different land forms with wiki links: 
{{w|Bay}}, {{w|Desert}}, {{w|Forest}}, {{w|Glacier}}, {{w|Hills}}, {{w|Island}}, {{w|Lagoon}}, {{w|Lake}}, {{w|Mesa}}, {{w|Mountains}}, {{w|Peninsula}}, {{w|Plain}}, {{w|River delta|Delta}}, {{w|River}}, {{w|Sea}}, {{w|Strait}} and {{w|Volcano}}.

==Transcript==
:[A colorful map shows various possible land forms which are labeled (and the last one with a spelling mistake included here). In general reading order the labels are:]
:Desert
:Mountains
:Sea
:Glacier
:Plain
:Island
:Volcano
:Lake
:River
:Delta
:Strait
:Hills
:Lagoon
:Bay
:Mesa
:Forest
:Penninsula

:[In the middle of these land forms, under the river and between the lake and the lagoon there is a black dot on the green bank of the lagoon with an arrow pointing it out. The arrow starts above the lake to the left of the glacier and is labeled:]
:My house

:[Below the panel there is a caption:]
:If I could live anywhere, I would choose the example map from geography books that explains what everything is called.

==Trivia==
*Randall has misspelled ''peninsula'' with an extra "n" as pe'''nn'''insula.

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Geography]]
[[Category:Maps]]
[[Category:Tornadoes]]
[[Category:Volcanoes]]

1471: Gut Fauna

2022-05-26T19:43:54Z

Green: Undoing vandalism

{{comic
| number = 1471
| date = January 9, 2015
| title = Gut Fauna
| image = gut_fauna.png
| titletext = I know it seems unpleasant, but of the two ways we typically transfer them, I promise this is the one you want.
}}

==Explanation==
The {{w|microbiome}} is the collection of bacteria that reside in the human digestive tract. The bacteria perform several vital digestive and immune-support functions. Different compositions of bacteria, collectively referred to as {{w|gut flora}}, can be linked to risk of some diseases, while other compositions are linked to a decreased risk of some diseases and are therefore called "good bacteria". The title "Gut fauna" is a play on words. ''Fauna'' means animal life in Latin, and ''flora'' means vegetable life. However, in this context ''flora'' means bacterial life because, when microscopes were invented, microbial life was considered to be non-animal and therefore classified as "flora". For a good description of the microbiome see [http://youtu.be/5DTrENdWvvM The Invisible Universe Of The Human Microbiome].

In this comic, [[Cueball]] is visiting a doctor ([[Ponytail]]) for some unknown problem. The doctor informs him that his gut macrobiome is out of balance, which Cueball responds to with confusion over whether or not she meant the microbiome or macrobiome. A macrobiome, instead of being composed of small organisms such as bacteria, would be composed of larger organisms such as mammals. The phrase "gut fauna" would refer to any animals living inside a gut (as the word fauna refers to animals living in an ecosystem).

Cueball is right to be worried by the doctor's reference to his macrobiome, as normal humans shouldn't have large animals living inside them{{Citation needed}} with the exception of some parasites such as {{w|Helminths}} or {{w|Cestoda}}, or in some cases, the {{w|Eating live animals|consumption of live animals}} such as octopus, shrimp and eels. No animals belong natively in the {{w|human digestive system}}; all known cases of animals living permanently in the human digestive system are causes of disease. His fear is compounded when the doctor prescribes one wolf for Cueball to swallow, which is normally impossible for average humans and would, at the very least, result in major interior (or exterior) damage to [[Cueball]] and (possibly) [[Ponytail]] when the wolf resists being swallowed. Needless to say this is not common physician practice due to the likely death rate.{{Citation needed}}

The choice of a wolf echoes the {{w|Wolf_reintroduction#Yellowstone_National_Park_and_Central_Idaho|reintroduction of the animals}} into the macrobiome of {{w|Yellowstone National Park}} in the United States, where they have improved the balance by, in part, preying on {{w|elk}} and reducing the damage caused by their grazing.

The dialog between the characters ends with the doctor asking the patient whether he needs a glass of water, a typical question asked by health professionals (water can help patients swallow oral medication). This last phrase further extends the humorous nature of the proposition to swallow the wolf by displaying a confidence of the doctor in her choice of the treatment modality. In reality, of course, drinking a glass of water while attempting to swallow a wolf would make the latter procedure neither easier, nor more feasible.

The title text suggests that swallowing the wolf is not the worst situation that could have occurred, as the doctor refers to "another way" that the wolf could be administered. One typical way that microbiomes are restored is through {{w|fecal bacteriotherapy}}, most easily described as a "poop transfer". It could also mean transferred via suppository. In either case, the worse "other way" that the doctor is referring to is thus likely the rectal route, which (for [[Randall]]) is less preferable than attempting to swallow a live wolf. However, either way would prove physically impossible and/or lethal.

If we are to take the doctor at her word that there is indeed some sort of macrobiome inside Cueball's gut, then perhaps she has some kind of matter compression ability that would make {{w|There Was an Old Lady Who Swallowed a Fly|introducing a live wolf}} a legitimate therapeutic option.

Randall has referenced {{w|wolf reintroduction}} programs before, in comic [[819: Five-Minute Comics: Part 1]].

==Transcript==
:[Cueball on an examining table; Ponytail wearing a doctor's coat holding some test results.]
:Doctor: I see the problem. Your gut macrobiome is out of balance. One moment.

:[Ponytail leaves.]
:Cueball: I think you mean '''''micro'''''biome... Right?

:[Ponytail returns, slightly disheveled, carrying a momentarily docile live wolf.]
:Doctor: No. Here, swallow this.
:Cueball: That's a wolf.
:Doctor: Do you need a glass of water?

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Animals]]
[[Category:Doctor Ponytail]]
[[Category:Medicine]]

1470: Kix

2022-05-26T19:43:41Z

Green: Undoing vandalism

{{comic
| number = 1470
| date = January 7, 2015
| title = Kix
| image = kix.png
| titletext = My parents sent me to several years of intensive Kix test prep.
}}

==Explanation==
This comic may be a commentary about the uselessness of brainstorming sessions or the bad ideas that come out of them, as they are often started with the phrase “there are no bad ideas”. As the brainstorming session continues the original meaning of the slogan is lost, much like a game of telephone, and the session becomes less productive.

{{w|Kix (cereal)|Kix}} is an American brand of cold breakfast cereal made of extruded and expanded cornmeal. Its slogan, "Kid tested, Mother approved," is well known in the United States, and is meant to suggest that children generally enjoy the cereal and their mothers, who are naturally concerned about the health of their children, approve of its ingredients. However, in this brainstorming session, the word "Approved" has apparently not yet been considered. A number of possible words and phrases for the ending have been presented and {{w|Strikethrough|stricken out}}, indicating that they were rejected; each one causes the slogan to be subject to increasingly absurd and comedic interpretations:

#'''Selected''': This word may have been chosen as a {{w|slant rhyme}} of "Tested". This word shares a definition with "Approved", and states that mothers specifically choose this cereal over others. This phrase could also suggest that one mother ''herself'' had been chosen for some unstated purpose.
#'''Perfected''': It's likely that the previous word inspired someone in the brainstorming session to find a similarly positive word that rhymes with "Selected". It states that one or more mothers were directly involved in developing and refining the cereal's composition to a high degree. Much like with "Selected", this could also suggest that the mother was somehow improved to perfection during the test.
#'''Not Notified''': Relates to the world of experimental research and clinical trials. This phrase suggests that the children who tested the cereal did not obtain the required consent, which would generally involve notifying and getting permission from both parents.
#'''Watching Helplessly''': Again we can see that in a brainstorming session such the previous option may trigger this one as it is related to the dangers of testing. This phrase suggests that mothers were forced to watch their children test the cereal, and that the cereal or the test is unhealthy or dangerous.
#'''Infected''': This may be intended to show the group dynamic of the brainstorming session as it is inspired by option one and two, as infected rhymes with both selected and perfected, and by the third option as both relate to dangerous testing. This slogan states that an infectious agent was passed to the mother as a result of the test. This could also be interpreted as the mother having introduced the infectious agent into the cereal or testing environment.
# '''Consumed''': Continuing the trend of dark slogans this slogan says that the mothers were ''themselves'' consumed, perhaps by their children (by virtue of the mother being an ingredient in the cereal), the cereal itself, or something otherwise related to the test. Another possible interpretation is that the mother ate the cereal after the kid tested it, possibly because the kid did not enjoy the taste.
#'''Fucker''': This expletive is often paired with "Mother" to form the compound word "Motherfucker". In this case, the slogan changes to {{w|vocative case}}: "[This cereal has been] Kid Tested, Motherfucker!". This appears to be an "elephant" - a ponderous ending of a joke that contrasts sharply with the refined and mild humor of the previous options. The phrase itself basically only states that a child tested the cereal and implies that nothing else matters. Using a swear word on packaging of a food designed for kids is usually not a good idea. {{Citation needed}}

The title text conflates the phrase "Kid tested" with college entrance exams such as the {{w|Standardized Aptitude Test}} (SAT) or the {{w|ACT (test)|ACT}}. Instead of stating that a child tasted the cereal and gave their opinion on its quality, the cereal itself is an academic subject on which the child was tested. Randall, referring to how some parents enroll their children in special {{w|Test prep|classes or schools}} to prepare them to score well in this type of test, states that his parents extensively prepared him for a college entrance exam about Kix cereal.

Cereal advertising has previously been referenced in [[38: Apple Jacks]].

==Transcript==
:[Ponytail, Megan, and Cueball are standing around a whiteboard on an easel; Ponytail and Cueball are holding red markers. The whiteboard reads:]
:[in Large] '''Kix'''
:[Underlined] Slogan ideas
:Kid Tested, Mother...

[following lines all in red and each crossed out]
:<s>Selected</s>
:<s>Perfected</s>
:<s>Not notified</s>
:<s>Watching helplessly</s>
:<s>Infected</s>
:<s>Consumed</s>
:<s>Fucker</s>

{{comic discussion}}

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

1460: SMFW

2022-05-26T19:42:50Z

Green: Undoing vandalism

{{comic
| number = 1460
| date = December 15, 2014
| title = SMFW
| image = smfw.png
| titletext = wtfw it's like smho tbfh, imdb.
}}

==Explanation==
Randall gives some examples of confusing acronyms that closely resemble more commonly-used acronyms. He depicts [[Cueball]] apparently puzzling over the meaning of one such acronym.

"SMFW", the title of the comic and an acronym used as the caption, is very close to a number of other common acronyms, including:

*"MFW", meaning "my face when..." used in similar sentence constructions to this comic's caption, to indicate that the image represents one's face when the specified thing happens.
*"SFW", meaning "safe/suitable for work", denoting that something does not have suggestive content.
*"SMH", meaning "shaking my head" or "so much hate", used to indicate dismay.
*"SMF", meaning "so much fun".
*"NSFW", meaning "not safe for work", the opposite of "SFW".

The title text contains more examples of imaginary acronyms of a similar nature:

*"WTFW" is a combination of "WTF" ("What the fuck") and "TFW" ("That feel when..." or "That face when...", used in a similar nature to "MFW"), and possibly "FTW" ("For The Win") and "FWIW" ("For What It's Worth").
*"SMHO" is a combination of "SMH" ("shake my head") and "IMHO" ([[1989:_IMHO|"In my humble/honest opinion..."]]).
*"TBFH" is a combination of "TBF" ("to be fair") and "TBH" ("to be honest").
*"IMDB" is, of course, [http://www.imdb.com/ the Internet Movie Database], but also resembles "IMHO".

Below are possible examples of potential (already existing, albeit rare) representations for each acronym, according to the {{w|Urban Dictionary}}:

*[http://www.urbandictionary.com/SMFW SMFW] is listed as an acronym for "Smoke more fucking weed".
*[http://www.urbandictionary.com/WTFW WTFW] is listed as an acronym for "What the fuck, what?".
*[http://www.urbandictionary.com/SMHO SMHO] is listed as an acronym for "Shaking my head off".
*[http://www.urbandictionary.com/TBFH TBFH] is listed as an acronym for "To be fucking honest".

Knowing Randall, the sentences given in the comic proper and title text were probably made without an actual meaning in mind. Nevertheless, the sentence in the comic has a very plausible interpretation: "So Much Frustration When an acronym ''almost'' makes sense." Other plausible interpretations of the acronym could be "So Much Fun When" or "See My Face When". Even the absurdly cryptic title text has a plausible translation: "What The Fuck, World? (WTFW) it's like Some Moron's Horrible Opinion (SMHO) To Be Fucking Honest (TBFH), I'm Done, Bye. (IMDB)".

==Transcript==
:[Cueball is sitting at a desk, crouched over a laptop.]
:[Caption below the panel:]
:SMFW an acronym ''almost'' makes sense

==Trivia==

The name of the comic ''[[xkcd]]'' is itself a false acronym – from the [http://www.xkcd.com/about xkcd about page]:
:''"It's not actually an acronym. It's just a word with no phonetic pronunciation -- a treasured and carefully-guarded point in the space of four-character strings."''

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Language]]

1452: Jurassic World

2022-05-26T19:40:42Z

Green: Undoing vandalism

{{comic
| number = 1452
| date = November 26, 2014
| title = Jurassic World
| image = jurassic_world.png
| titletext = Hey guys! What's eating you? Ha ha ha it's me! Oh, what fun we have.
}}

==Explanation==
This strip refers to ''{{w|Jurassic World}}'', the then new ''{{w|Jurassic Park}}'' movie, and the titular theme park. [[White Hat]] explains to [[Megan]] that, in their park, they have genetically engineered a better {{w|Tyrannosaurus}}. Megan doesn't feel that the historic Tyrannosaurus can be improved upon, but White Hat insists they've created an even more terrifying, smarter ''Tyrannosaurus'' for this new park.

White Hat refers to ''Tyrannosaurus'' as "two decades old", indicating that he has switched topics from the movie's plot line to the animation techniques that created the {{w|Jurassic Park (film)|Tyrannosaurus on-screen}} in 1993 versus today. Clearly, in the computer animation world, we should be able to create something more convincing with modern technology. Megan comments that she is fairly certain it is older than two decades, suggesting that she is referring to the actual Tyrannosaurus that lived millions of years ago.

In the final panel, White Hat introduces the "new" ''Tyrannosaurus'', who is immediately recognizable as the green ''Tyrannosaurus'' from {{w|Ryan North|Ryan North's}} ''{{w|Dinosaur Comics}}''; specifically, from the last panel of said webcomic - which in turn is from [http://www.smithsonianmag.com/science-nature/interview-with-ryan-north-creator-of-dinosaur-comics-15523444/ clip art]. Anyone who has read so much as a handful of ''Dinosaur Comics'' will know that its ''Tyrannosaurus'' character "T-Rex" is about as far from smart and scary as it is possible for a ''Tyrannosaurus'' to be (see [http://www.qwantz.com/index.php?comic=2739 this example] from the day this comic was released).

The title text is an example of what T-Rex (the character) would say to a couple of humans, and it's a poor joke which would only be funny when it's a talking T-Rex saying it. Despite his goofy mannerisms, he is still a carnivore who attacks (or at least accidentally steps on) humans, as can be seen in panel 3 and 4 of the webcomic.

==Transcript==
:[White Hat holding one hand up in front om him and Megan are walking together.]
:White Hat: In ''Jurassic World'', we've used genetic engineering to create a ''better'' dinosaur.
:Megan: Tyrannosaurus is the most charismatic animal that ever lived, and you think you'll ''upstage'' it?

:[White Hat now holds both his hands up in front of him as he and Megan walk on.]
:White Hat: ''Tyrannosaurus'' was cool, but it's two decades old!
:Megan: I think it's a ''little'' older than that.

:[In this frame-less panel White Hat points up as they continue to walk.]
:White Hat: We took ''Tyrannosaurus'' and we ''improved'' it. Made it scarier, deadlier, smarter.
:White Hat: Look–there it is!

:[White Hat (drawn without his hat) and Megan are dwarfed in the bottom left corner as they stare up at a facsimile of the green T-Rex from ''Dinosaur Comics''. They only reach T-Rex to it's knees.]

==Trivia==
*In the last panel [[Randall]] forgot to draw White Hat's hat so he looks like [[Cueball]], but from the first panel where White Hat walks with Megan and points up at the Dinosaur, it is clear that it is those two characters that are standing beneath it in this last panel.
**Note that in the two other comics with T-Rex, Randall put in a small Cueball under the foot of T-Rex in the fourth panel of [[145: Parody Week: Dinosaur Comics]], and in the T-Rex [http://xkcd.com/1350/#p:f2b12f1e-bbae-11e3-801c-002590d77bdd story line] from [[1350: Lorenz]], he also forgot to drawn [[Hairy|Hairy's]] hair, thus also there including Cueball though like here by mistake...

The entire ''Dinosaur Comics'' was parodied in [[145: Parody Week: Dinosaur Comics]], where Randall copied the drawings himself, and T-Rex has appeared in one of the story lines in [[1350: Lorenz]] (see this [http://xkcd.com/1350/#p:f2b12f1e-bbae-11e3-801c-002590d77bdd example story line] and also the Dinosaur section under [[1350:_Lorenz#Themes|Lorenz themes]]), where the actual images from the first three panels of Ryan's comic are used, just like here where it is the last panel which is used.

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Megan]]
[[Category:Dinosaurs]]
[[Category:Jurassic Park]]

1453: fMRI

2022-05-26T19:39:32Z

Green: Undoing vandalism

{{comic
| number = 1453
| date = November 28, 2014
| title = fMRI
| image = fmri.png
| titletext = They also showed activation in the parts of the brain associated with exposure to dubious study methodology, concern about unremoved piercings, and exasperation with fMRI techs who won't stop talking about Warped Tour.
}}

==Explanation==
{{w|Functional magnetic resonance imaging}} (fMRI), as the name suggests, is an offshoot of the MRI. It shows brain activity, typically while the subject is performing tasks or responding to stimuli. During the test, the subject is laid in a relatively small cylinder inside a big, very loud, machine which produces extremely strong magnetic fields. To prevent damage or injury, the subject must remove all metal objects from their body, including piercings, jewelry, watches, etc.

In the tests shown, the brain activity detected is a direct result of the testing environment itself, and has nothing to do with the simple tasks being performed by the subject. During fMRI participants hear loud noises, are confined in a small space (thus the claustrophobia) and have removed their jewelry. The researcher has mistaken these associated brain activities as effects as being caused by ''performing simple memory tasks'' which the participants have been asked to do and not a direct result of the settings of the test. Thus, the brain areas described by Megan are those associated with taking a functional MRI scan, rather than those associated with the "test" supposedly being carried out. The results being shown are known as {{w|Artifact_(error)|artifacts}}, which are shown later in [[1781: Artifacts]].

In real experiments, reported activity patterns are always a result of subtracting average brain activity from many samples gathered during task from so called ''resting-state'' activity - which is obtained while subjects are not engaged in any task, thus eliminating the effect the setting has on brain activity. Apparently, the researcher in the comic has failed to account for that in the analysis of the data.

The title text raises the more difficult and controversial issues of methodology, saying that the subjects ''also showed activation in the parts of the brain associated with exposure to dubious study methodology''. Here [[Randall]] makes fun of the overly confident, sweeping statements made by some fMRI researchers, often in the press. Of course, fMRI technique requires that the researcher account for several possible sources of errors by, among others, performing proper statistical analyses, multiple comparisons and using proper control groups. These are usually the reasons for {{w|Functional magnetic resonance imaging#Criticism|fMRI criticism}}. See the link for further information, including a famous ironic study of a dead salmon which was shown various pictures of people while fMRI scans were made. The scans could be interpreted as showing meaningful brain activity, unless the {{w|multiple comparisons problem}} was properly addressed. Randall has previously made fun of geographic profiles falling to this trap in comic [[1138: Heatmap|1138]].

The title text then continues with the jewelry issue, now especially the ''concern about unremoved piercings''. In the worst case these could be ripped off by the strong magnetic field. So it could be of some concern - especially when you take into consideration some of the places people may have piercings that are not obvious to the MRI personnel! The final remark about activation regards ''exasperation with fMRI techs who won't stop talking about Warped Tour''. "{{w|Warped Tour}}" refers to a traveling music festival that has been going since 1995, originally as a punk rock festival, but now with a more diverse set of music. Due to the nature of {{w|Moshing|Mosh Pits}}, the loud, cacophonous music, the facial jewelry of concert-goers and the tight quarters of the pit make it similar in description to an MRI.

==Transcript==
:[Megan talking to an unseen audience in front of an fMRI brain scan.]
:Megan: Our fMRI study found that subjects performing simple memory tasks showed activity in the parts of the brain associated with loud noises, claustrophobia, and the removal of jewelry.

{{comic discussion}}
[[Category:Comics with color]]
[[Category:Comics featuring Megan]]
[[Category:Psychology]]
[[Category:Science]]

1454: Done

2022-05-26T19:38:48Z

Green: Undoing vandalism

{{comic
| number = 1454
| date = December 1, 2014
| title = Done
| image = done.png
| titletext = I'm sorry, but the author of this Facebook comment clearly believes you were.
}}

==Explanation==
This comic is a joke about the hyperbolic expression ''shut it down'' being taken literally. If someone thinks that a device has achieved its goal they shut it down. After an idea or product that people think is well made is created people will joke that the process that created it should be shut down, as if the process has achieved its ultimate purpose. This is most often used sarcastically for an inferior product or idea. Taking things literally is a common theme in the xkcd comics.

Curly-hair sits at a computer anxiously and nervously writing a message to someone she cares about deeply, possibly a child to be adopted or a romantic interest. Curly-hair plans on saving enough money to have the person flown to her location from "half a world away." Curly-hair ends the message with a promise to communicate daily until the two are able to meet. When attempting to send the message, however, Curly-hair discovers that their internet connection is down and the message goes unsent.

[[Ponytail]] explains there was a "ridiculous video" to which someone had commented "That's it. Shut down the Internet. We're done." This was taken literally and, because enough people agreed with this comment, the internet was shut down and Curly-hair was left unable to communicate with her love.

The joke being that the internet was creating something far more valuable between Curly-hair and her love than a ridiculous video, thus highlighting the beautiful and far reaching potential impact of the internet. The likelihood of the entire internet being shut down based on a single comment being vanishingly low adds to the humor.

In the final panel Curly-hair states wistfully that she was not done with the internet. The title text is Ponytail's response, which asserts Ponytail's belief that Curly-hair's message could not be important because the Facebook comment asserted that nothing of any significance could come from the internet after the ridiculous video.

==Transcript==
:Writer (typing): I had started to think I was asking too much, that I needed to settle. And then I found you half a world away.

:Writer (typing): I've been saving money. Six months from now, I'll be able to fly you here and support us for a while.

:Writer (typing): It's a long wait, but we'll talk every day until then. Maybe this won't work out, but I want to try. What do you think?

:Computer: '''ERROR''': Your message could not be sent.
:''[Refresh]''
:Computer: '''ERROR''': No connection.
:Writer: ??

:Writer: Why can't I connect?
:Ponytail: Someone saw a ridiculous video and said "That's it. Shut down the Internet. We're done." So they did.

:Writer: ...But... I wasn't done.

{{comic discussion}}
[[Category:Comics featuring Ponytail]]
[[Category:Internet]]
[[Category:Romance]]

1455: Trolley Problem

2022-05-26T19:38:26Z

Green: Undoing vandalism

{{comic
| number = 1455
| date = December 3, 2014
| title = Trolley Problem
| image = trolley_problem.png
| titletext = For $5 I promise not to orchestrate this situation, and for $25 I promise not to take further advantage of this ability to create incentives.
}}

==Explanation==
The {{w|trolley problem}} is a thought experiment often posed in {{w|philosophy}} to explore moral questions, with applications in {{w|cognitive science}} and {{w|neuroethics}}. The general version is that an out of control trolley (or train) is heading towards 5 people on the track who can't get out of the way. On an alternative branch of the track is 1 person who can't get out of the way. The trolley can be diverted by using a lever, with the consequence of saving the 5 people but killing the 1 person.

The choice is between a deliberate action that will directly kill one person, or allowing events to unfold naturally, resulting in five deaths. The question posed is whether or not it is morally right to pull the lever. The moral question is not as simple as it may first appear.

This results of [http://www.philosophyexperiments.com/fatman/Default4.aspx this test] report that around 86% of respondents choose the utilitarian option of diverting the trolley.

There are, however, several alternative formulations of the same basic dilemma. One such scenario allows you to stop the trolley by deliberately pushing "a very fat man" into its path, killing the man but saving the other five people. Another scenario involves selecting a healthy young and innocent person to die, in order to save five others going through organ donation. In both of these examples the basic dilemma is the same. However, most people reject the utilitarian option in these cases.

After discovering a variation on this problem posed in a strip of the [http://www.smbc-comics.com/?id=3556#comic Saturday Morning Breakfast Cereal] webcomic (which can be seen on the tablet he is carrying), [[Rob|Cueball]], Black Hat's roommate, presents it to [[Black Hat]]. Before Cueball can finish explaining the problem, most notably leaving out the disadvantage to flipping the lever where it would kill one person, Black Hat questions whether he would need to get up to reach the lever and how much it would interrupt his other activities. As usual, he cares nothing at all about what happens to other people. This response is linked to another theory in philosophy, that of {{w|self interest}} or {{w|egoism}} or {{w|Objectivism (Ayn Rand)|Objectivism}}, in which a person will choose the action with the most benefit for them personally.

Black Hat then poses an offer: he promises to divert the trolley if Cueball is one of the five endangered people, provided that Cueball pays him $1 now. Again Black Hat is twisting the situation to his own benefit, in this case monetary. In the case of self-interest, the $1 could be the price at which Black Hat values his time and effort, below which he feels there is no benefit to himself in pulling the lever. Cueball decides that there is no point posing the problem to someone like Black Hat and gives up. This further shows that it is challenging for people with different ethical frameworks to function together without a common understanding, either mutually or with one side using that understanding to motivate a mutually agreeable or horrible solution.

The title text follows this up by continuing Black Hat's offers. For $5 he will not deliberately arrange this situation and for $25 he will quit looking for further incentives. These attempts to exploit the thought exercise for personal gain further demonstrate Black Hat's cynical amorality.

Black Hat's offer makes Cueball himself the subject of the trolley problem: Cueball now has a choice of expending $1 to save 5 people while sacrificing one person, or $5 to save all 6 people. Of course, he could dismiss the offer as a joke, if not for the person making it, which, as we know from other comics, is very much capable of such exploits.

==Transcript==
:Cueball: Ever heard of the trolley problem?
:Black hat: No. What is it?

:Cueball: A trolley is barreling towards five helpless people on the tracks. You can pull a lever to direct it onto another track, but-

:Black hat: Can I reach the lever without getting up?
:Cueball: Wait, I'm not-
:Black hat: In this scenario, how busy am I?

:Cueball: I guess I forgot who I was talking to.
:Black hat: For a dollar, I'll promise to pull the lever if one of the five people is you.

==Trivia==
*Three years later two comics were released with about one month between them where the Trolley problem was mentioned. In [[1925: Self-Driving Car Milestones]] it is in the last ''milestone'' on the list and a month later, in [[1938: Meltdown and Spectre]], it is used as a metaphor for the way some computer programs work.

{{comic discussion}}
[[Category:Comics featuring Black Hat]]
[[Category:Comics featuring Cueball]]
[[Category:Philosophy]]
[[Category:Comics with color]]

1459: Documents

2022-05-26T19:37:22Z

Green: Undoing vandalism

{{comic
| number = 1459
| date = December 12, 2014
| title = Documents
| image = documents.png
| titletext = Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Copy of Untitled.doc
}}

==Explanation==
When saving documents, the user is typically prompted to choose a filename, which may seem like a trivial choice. However, the filename is often the primary way of identifying the document you are looking for, and a descriptive title is of huge benefit when trying to find a certain document. Those who are too rushed or too lazy to create a useful filename, or those who don't understand what constitutes a useful filename are setting themselves up for future frustration.

When a user creates a new copy of a file in the same directory, the operating system may automatically append "copy" or "Copy of" to the filename. Subsequent copies of the file have "copy 2", "copy 3", etc. appended. When searching documents later, the user may struggle to remember which copy is the correct one to use.

This comic portrays a person, in this case [[White Hat]], who has taken such a naming convention to an extreme, giving hundreds of documents essentially the same confusing or useless filename. [[Cueball]] appears to have a severe distaste for this convention (or may just be in shock at how one could be so lazy or incompetent in the short term to suffer through or ignore the consequences in the long term) and hence provides a [http://knowyourmeme.com/memes/protip protip] to never look in someone else's documents folder for the fear of finding these irritating details.

The .doc and .docx extensions are given to documents created in Microsoft Word, with .docx being the default option from Microsoft Office 2007 onwards. When first saving a document, many programs will default to "Untitled", adding numbers to the end as more are created. However, in Microsoft Word the default filename is the first sentence of the document; if the document is still empty, the default filename is "Doc1" with the number increasing each time. In order to get such a file directory, White Hat would have to manually title all of his documents "Untitled". He appears to frequently make copies, and occasionally made copies of the copies, only very rarely adding a keyword to the file name like "important".

In some cases he has added a minimal amount of detail to the filename, though hasn't removed the redundant "untitled copy" portion, which probably only adds to Cueball's frustration, as it demonstrates that White Hat does have at least a basic understanding of the importance of meaningful filenames, but still hasn't made any attempt to address the systemic problem.

The ''Untitled 40 MOM ADDRESS.jpg'' is an image file (jpg), not something that would normally be used to store someone's address, though it could be a map or a picture of an envelope. It is the first jpg file on the list, but that last full filename is also a jpg with number 41, and below in the "speech" line down to the PC the next three files have number 42, 43 and something beginning with 4. So here the numbering of jpg files continue.

The .doc numbering goes from 241 to 243, and then 243 IMPORTANT. The .docx only increases from 138 to 139, but there are two extra copies of the 138 document.

The filenames are not in alphabetical order as 241 and 40 falls out of place. This likely means that there is no automatic sorting all (i.e., they are sorted by hand), or that they are sorted by time stamp. Sorting by timestamp can be very useful, especially if you use White Hat's naming scheme. But this also means that he still uses .doc (copies old files) after he has obtained the new Microsoft Office 2007 that used .docx.

The title text can refer to one of two common quirks in Windows/Office. One is of copying and pasting within the same folder on a Windows PC. The copy of the file will default to the name "Copy of <original title>", a second copy becomes "Copy of Copy of <original title>" and so forth. The other common quirk that can produce file names like this relates to how Microsoft Office handles downloaded file(s) that are not saved (i.e. "Open" instead of "Save"), the file is actually saved in a temporary folder allowing you to look at and/or edit the file - usually with restrictions on doing so until you actually save a copy in an actual folder somewhere. Oftentimes, especially within an office network where files are passed around via email, the other person may just open a file, editing it, then proceeding to save it as required. Upon attempting to save, the program will prompt one to "Save a copy of the original file", as the original file was never actually saved on the hard drive but just opened from a temporary folder, adding the phrase "copy of" to the filename, regardless of its final location. Forwarding this file will continue this trend adding the phrase "copy of" every time someone opens, edits then saves the file (rather than save the file then edit it), thus creating repetitive use of "copy of" within the same name. In a file that is heavily edited and passed around via email like this, if care is not taken to edit the file name, the name may get up to 5 or 6 repeats of the phrase "copy of".

It is rather extreme to get to a 33rd copy of the original untitled.doc file as shown here, however, as a result the file name is 276 characters long (including the four from the .doc extension), an impossible file name in most operating environments because it is too long. 255 characters is the limit for any file or folder name in Linux, and is the limit for a fully defined file name (file name, extension and the full folder path in which the file is stored in) in Windows. So the file name is 22 characters too long for Linux and at least 25 characters too long for Windows since being in the root of drive takes 3 characters, each folder adds at least 2 characters (one chosen and the backslash). Whereas such long names for a file may be uncommon, it is not uncommon in Windows that users run out of characters for the full name and path, if they have several sub folders.
Note that when performing this type of copying on Windows 7, the new file is named "<original name>_2", not "Copy of <original name>".

==Transcript==
:[White Hat is sitting at his PC. Cueball stands behind him looking over his shoulder at the screen.]
:PC: Untitled 138.docx
:: Untitled 241.doc
:: Untitled 138 copy.docx
:: Untitled 138 copy2.docx
:: Untitled 139.docx
:: Untitled 40 MOM ADDRESS.jpg
:: Untitled 242.doc
:: Untitled 243.doc
:: Untitled 243 IMPORTANT.doc
:: Untitled 41.jpg
:[The remaining file names are only partially visible through the tail of the PC's "speech" bubble.]
::::  42
::::  43
::::  4

:Cueball: ''Oh my god.''

:[Caption below the panel:]
:Protip: Never look in someone else's documents folder.

{{comic discussion}}
[[Category:Protip]]
[[Category:Comics featuring White Hat]]
[[Category:Comics featuring Cueball]]

1461: Payloads

2022-05-26T19:35:39Z

Green: Undoing vandalism

{{comic
| number = 1461
| date = December 17, 2014
| title = Payloads
| image = payloads.png
| titletext = With a space elevator, a backyard full of solar panels could launch about 500 horses per year, and a large power plant could launch 10 horses per minute.
}}

A larger version of the image can be found [http://imgs.xkcd.com/comics/payloads_large.png here].

==Explanation==
This comic is an infographic representing the launch mass of various spacecraft and artificial satellites, and the {{w|Low Earth orbit|low Earth orbit}} payload capacity of various space launch vehicles. Rather than using standard units of mass such as kilograms or pounds, Randall has assigned values based on the mass of a horse. Based on cross checking researched masses and payloads with the number of horses depicted, it appears that one horse unit is defined as 450 kg (with an average of 432.82 kg), or perhaps 1000 lb. In cases where the mass is less than one horse, an alternative measure of dogs has been used, where one dog appears to be roughly 40 kg (with an average of 48.05 kg, or perhaps 100 lb.). In the case of {{w|Vanguard 1}}, even a dog is too large a measure, so instead the unit squirrel is used to represent its 1.47 kg (3.5 lb.?) mass.

The overall comic may be an allusion to {{w|horsepower}}, a similar-sounding but completely different concept. Horsepower is a measurement of {{w|power (physics)|power}} ({{w|work (physics)|work}} per unit time). Another commonly referenced unit for power is the {{w|watt}}. 1 horsepower is meant to be approximately the amount of power a horse can deliver. In contrast, Randall uses the horse to measure {{w|mass}} (of particular spacecraft, and of the maximum payload launch vehicles can carry).

The top pane of the comic (black background) shows the mass of various spacecraft, while the bottom (white background) shows the payload capacity (to low Earth orbit) of launch vehicles. Along the bottom of the image is a timeline, relating to the launch date of the entries.

There are also several joke insertions:
*T-Rex - A dinosaur, but fairly unlikely to be found orbiting Earth.
*Pegasus - An actual {{w|Pegasus (rocket)|launch vehicle}}, but also the name of a {{w|Pegasus|mythical flying stallion}}. The payload is given as "one Pegasus", which comes out to be slightly less than "one horse".
*Atlas-Centaur - Again, an actual {{w|Atlas-Centaur|launch vehicle}}, but also a reference to the half-human half-horse creatures of Greek mythology. The payload is given in "centaurs", which come out to be slightly more than "horses".
*1981 {{w|Oldsmobile}} - Not a launch vehicle, but in fact a car. The payload is given as 4 horses, which may relate to the carrying capacity (by weight) of the Oldsmobile, not the ability of an Oldsmobile to launch that payload into low Earth orbit. While there are no known examples of an Oldsmobile reaching low Earth orbit, {{w|The Blues Brothers (film)|''The Blues Brothers''}} movie shows an Oldsmobile performing a very, very long flight, and this might be the reason why Randall chose this specific car.

The Pegasus, 1981 Oldsmobile, and Stratolaunch spacecraft are depicted horizontally, because these vehicles launch from a horizontal starting position and use forward momentum to facilitate their launch.

An unlabelled launch vehicle is shown below the H-IIA near 2002. From the payload and date it is believed to represent the {{w|Delta IV#Delta IV Medium|Delta IV M}}. Whether its lack of labelling is intended or a mistake is unknown.

The title text refers to a favourite subject of Randall's - The {{w|space elevator}}. A space elevator is a (currently theoretical) mechanism for travelling into space, consisting of a very long (>35,000 km) cable and counterweight connected to the Earth at the equator. The cable rotates at the same rate as the earth, and thus appears stationary when viewed from earth. It is then possible to climb the cable into space, and even use it as a slingshot to launch vehicles.

In the title text, the amount of power required to lift a horse into space has been investigated, with the launch capacity of a backyard solar array and large power station compared. The orbit to launch horses is not precised, though; from the space elevator, the only circular orbit easily achievable is geostationary orbit, and getting into Low Earth Orbit is only slightly easier than without the elevator. Assuming the lowest stable orbit (that is, above the atmosphere), required power output of the solar array is about 315-350 kW and the power station at 3.3-3.7 GW.

===Tables===
The tables below contain data relating to each entry on the comic image.

*Name - Should be as shown in the comic
*Launch date - Date of first flight
*Mass/payload (horses) - Value as given in comic
*Mass/payload (kg) - Independently researched value

Where the researched launch date or mass/payload don't seem to match the comic, they should be identified with ?

{|
|- style="vertical-align:top;"
|
{| class="wikitable sortable"
!colspan="4"|Spacecraft mass
|-
!Spacecraft
!Launch date ''{{w|ISO 8601}}''
!Mass (horses)
!Mass (kg)
|-
|{{w|Sputnik 1|Sputnik}}[http://www.astronautix.com/craft/sputnik1.htm]
|1957-10-04
|2 Dogs
|83.6
|-
|{{w|Vanguard 1}}[http://www.astronautix.com/craft/vanuard1.htm]
|1958-03-17
|Squirrel
|1.47
|-
|{{w|Pioneer 5}}[http://www.astronautix.com/craft/pioneer5.htm]
|1960-03-11
|Large Dog
|43
|-
|{{w|Venera 1}}[http://www.astronautix.com/craft/venra1va.htm]
|1961-02-12
|1
|643.5
|-
|{{w|Mariner 2}}[http://www.astronautix.com/craft/marner12.htm]
|1962-08-27
|3 Dogs
|202.8
|-
|{{w|Apollo Command/Service Module|Apollo}}[http://www.astronautix.com/craft/apolocsm.htm]
|1964-05-28
|67
|30,329
|-
|{{w|Venera 7}}[http://www.astronautix.com/craft/ven3vv70.htm]
|1970-08-17
|3
|1,180
|-
|{{w|Pioneer 10}}[http://www.astronautix.com/craft/pior1011.htm]
|1972-03-03
|7 Dogs
|258.8
|-
|{{w|Skylab}}[http://www.astronautix.com/craft/skylab.htm]
|1973-05-14
|171
|77,088
|-
|{{w|Venera 9}}[http://www.astronautix.com/craft/venra4v1.htm]
|1975-06-08
|11
|4,936
|-
|{{w|Voyager 2}}[http://www.astronautix.com/craft/voyager.htm]
|1977-08-20
|2
|800
|-
|{{w|Space Shuttle|Shuttle (Total)}}[http://www.braeunig.us/space/specs/orbiter.htm]
|1981-04-12
|206
|104,328?
|-
|{{w|Space Shuttle|Shuttle (Payload)}}
|1981-04-12
|54
|24,400
|-
|{{w|Mir}}
|1986-02-20
|288
|129,700
|-
|T-Rex
|N/A
|15
|6,800
|-
|{{w|Hubble}}[http://www.astronautix.com/craft/hst.htm]
|1990-04-24
|25
|11,110
|-
|{{w|Compton Gamma Ray Observatory}}[http://www.astronautix.com/craft/gro.htm]
|1991-04-05
|38
|17,000
|-
|{{w|Corona (satellite)|Keyhole 3}}†
|1961
|40
|1150
|-
|{{w|International Space Station}}
|1998
|932
|450,000
|-
|{{w|Cassini-Huygens|Cassini}}
|1997-10-15
|11
|5,300
|-
|{{w|Huygens (spacecraft)|Huygens Lander}}
|1997-10-15
|1
|319
|-
|{{w|Rosetta (spacecraft)|Rosetta}}
|2004-03-02
|6
|2,900
|-
|{{w|Opportunity (rover)|Opportunity}}
|2003-07-07
|5 Dogs
|185
|-
|{{w|Dawn (spacecraft)|Dawn}}[http://www.astronautix.com/craft/dawn.htm]
|2007-09-27
|3
|1,240
|-
|{{w|TerreStar-1|Terrastar}}*
|2009-07-01
|15
|6,910
|-
|{{w|Dragon (spacecraft)|Dragon}}[http://www.astronautix.com/craft/dragon.htm]
|2010-06-04
|17
|8,000
|-
|{{w|Tiangong-1}}
|2011-09-29
|19
|8,506
|-
|{{w|Curiosity (rover)|Curiosity}}
|2011-11-26
|2
|900
|-
|{{w|KH-7 Gambit|Keyhole 7}}†
|1963-07-12
|40
|2000
|-
|{{w|Orion (spacecraft)|Orion (Capsule)}}
|2014-12-05
|20
|8,913
|-
|{{w|James Webb Space Telescope|James Webb Telescope}}
|2018-08 (Projected)
|14
|6,200
|-
|{{w|Orion (spacecraft)|Orion}}
|2014-12-05
|20
|8,913
|-
|{{w|Orion Service Module}}
|2017 (Projected)
|25
|12,000
|-
|{{w|Deep Space Habitat|Orion Deep Space Habitat}}
|2021 (Projected)
|65
|28,750 & 45,573
|}
<nowiki>*</nowiki>Terrastar is believed to be a misspelling of {{w|TerreStar-1|TerreStar}}, based on its mass and launch date.

<nowiki>†</nowiki>Keyhole 3 and 7 seem to be errors; Keyhole 3 satellites were launched between 1961 and 1962 and Keyhole 7 between 1963 and 1967. 
The dates and masses in the comic more closely correspond to the {{w|KH-11 Kennan|Keyhole 11}}.
|

{| class="wikitable sortable"
!colspan="4"|Launch vehicle capacity
|-
!Spacecraft
!Launch date ''{{w|ISO 8601}}''
!Payload (horses)
!Payload (kg)
|-
|{{w|Sputnik (rocket)|Sputnik Launcher}}[http://www.astronautix.com/lvs/spuk71ps.htm]
|1957-10-04
|1
|500
|-
|{{w|Thor-Able|Thor}}
|1958-04-24
|3 Dogs
|120
|-
|{{w|Mercury-Atlas}}
|1960-07-29
|3
|1,360
|-
|{{w|Saturn I}}
|1961-10-27
|20
|9,070
|-
|{{w|Proton-K}}[http://www.astronautix.com/lvs/protonk.htm]
|1967-03-10?
|44
|19,760
|-
|{{w|Atlas-Centaur}}[http://www.astronautix.com/lvs/atlntaur.htm]
|1962-05-08
|8 Centaurs
|3,630
|-
|{{w|Titan IIIA}}
|1964-09-01
|7
|3,100
|-
|{{w|Saturn IB}}
|1966-02-26
|45
|21,000
|-
|{{w|Soyuz (rocket)|Soyuz}}
|1966-11-28
|14
|6,450
|-
|{{w|Saturn V}}
|1967-11-09
|262
|118,000
|-
|{{w|Black Arrow}}
|1969-06-27
|4 Dogs
|135
|-
|{{w|N1 (rocket)|N1}}
|1969-02-21
|211
|90,000?
|-
|{{w|Long March 1}}
|1969-11-16
|2
|300*
|-
|{{w|N-I (rocket)|N-I}}
|1975-09-09
|4
|1,200?
|-
|{{w|Delta 0100|Delta 0900}}
|1972-07-23
|3
|1,300
|-
|{{w|Ariane 1}}
|1979-12-24
|3
|1,400
|-
|{{w|Satellite Launch Vehicle|SLV}}
|1979-08-10
|1 Dog
|40
|-
|{{w|N-II (rocket)|N-II}}
|1981-02-11
|4
|2,000
|-
|{{w|Oldsmobile#1970s-1980s|1981 Oldsmobile}}
|1981
|4
|N/A (Model dependent)
|-
|{{w|ASLV}}
|1987-03-24
|4 Dogs
|150
|-
|{{w|Long March 4A}}
|1988-09-06
|9
|4,000
|-
|{{w|Ariane 4}}
|1988-06-15
|16
|5,000-7,600?
|-
|{{w|Shavit}}
|1988-09-19
|6 Dogs
|350-800?
|-
|{{w|Energia}}
|1987-05-15
|218
|100,000*
|-
|{{w|Pegasus (rocket)|Pegasus}}
|1990-04-05
|1 Pegasus
|443
|-
|{{w|Atlas I}}[http://www.astronautix.com/lvs/atlasi.htm]
|1990-07-25
|13
|3,630?
|-
|{{w|PSLV}}
|1993-09-20
|8
|3250
|-
|{{w|J-I}}[http://www.astronautix.com/lvs/j1.htm]
|1996-02-11
|2
|850
|-
|{{w|Long March 3B}}
|1996-02-14
|27
|12,000
|-
|{{w|H-IIA}}
|2001-08-29
|22
|10,000
|-
|(unlabelled) {{w|Delta IV#Delta IV Medium|Delta IV M}}?*
|2002-09-20
|21
|4200-6882
|-
|{{w|Delta IV Heavy|Delta IV-H}}[http://www.astronautix.com/lvs/delheavy.htm]
|2004-12-21
|64
|28,790
|-
|{{w|Falcon 1}}
|2006-03-24
|1
|670 (Proposed)
|-
|{{w|Ariane 5#Variants|Ariane 5ES}}[http://www.astronautix.com/lvs/arine5es.htm]
|2008-03-09
|47
|21,000
|-
|{{w|H-IIB}}
|2009-09-10
|37
|19,000?
|-
|{{w|Unha}}
|2009-04-05
|2 Dogs
|100[http://www.ucsusa.org/sites/default/files/legacy/assets/documents/nwgs/Wright-Analysis-of-NK-launcher-3-18-09.pdf]
|-
|{{w|Atlas V|Atlas V 541}}
|2011-11-26
|38
|17,443[http://www.lockheedmartin.com/data/assets/ssc/cls/AVUG_Rev11_March2010.pdf]
|-
|{{w|Falcon 9}}
|2013-09-29
|29
|13,150
|-
|{{w|Antares (rocket)|Antares}}
|2013-04-21
|14
|6,120
|-
|{{w|Stratolaunch carrier aircraft|Stratolaunch}}
|2016 (Projected)
|14
|6,100
|-
|{{w|Falcon Heavy}}
|2018-02-06
|118
|53,000
|-
|{{w|Space Launch System|SLS Block 1}}
|2018-11 (Projected)
|156
|70,000[http://www.nasa.gov/pdf/664158main_sls_fs_master.pdf]
|-
|{{w|Space Launch System|SLS Block 1B}}
|2021 (Projected)
|217
|100,000?
|-
|{{w|Space Launch System|SLS Block 2}}
| 2030's (Projected)
|289
|130,000[http://www.nasa.gov/pdf/664158main_sls_fs_master.pdf]
|}

*The unlabelled launch vehicle is believed to be the Delta IV M, based on its payload and date.
|}

==Transcript==
:[This comic is a wide drawing, with a larger drawing that can be reached by clicking the small picture on xkcd. In the smaller picture shown on xkcd only the text that is not red can be read. The transcript below is thus for the large drawing. It is divided into three horizontal sections. The first section is black and shows spacecrafts, the second is white and shows launch vehicles, and the third is black again showing a timeline ranging from 1950 to the future. The vehicles are shown by the proper number of horses, and when that weight is less than one full horse also in the weight of other smaller animals.]

:[The black section:]
:<big><big>Spacecraft mass</big></big>
:<big>Measured in horses</big>

:Sputnik -- <1 horse (2 dogs )
:Vanguard 1 -- <1 horse (Squirrel )
:Pioneer 5 -- <1 horse (Large dog)
:Mariner 2 (United States) -- <1 horse (3 dogs )
:Venera 1 (USSR) -- 1 horse
:Apollo -- 67 horses
:Venera 7 -- 3 horses
:Pioneer 10 -- <1 horse (7 dogs)
:Skylab -- 171 horses
:Venera 9 -- 11 horses
:Voyager 2 -- 2 horses
:Shuttle (Total) -- 206 horses
:Shuttle Payload -- 54 horses
:Mir -- 288 horses
:T-Rex -- 15 horses
:Hubble -- 25 horses
:Compton Gamma Ray Observatory -- 38 horses
:Keyhole 3 -- Spy satellite
:International Space Station -- 932 horses
:Cassini -- 11 horses
:Huygens lander -- 1 horse
:Rosetta -- 6 horses
:Opportunity -- <1 horse (5 dogs)
:Dawn -- 3 horses
:Terrastar -- 15 horses
:Dragon -- 17 horses
:Tiangong-1 -- 19 horses
:Curiosity -- 2 horses
:Keyhole 7 -- 40 horses
:Orion (capsule) -- 20 horses
:James Webb Telescope -- 14 horses
:[20 horses:]
:Orion
:[25 horses:]
:Orion Service Module
:[65 horses:]
:Orion Deep-Space Habitat

:[The white section:]
:<big><big>Launch vehicle capacity</big></big>
:(Payloads to low earth orbit)
:<big>Measured in horses</big>

:Sputnik Launcher -- 1 horse
:Thor -- <1 horse (3 dogs)
:Mercury-Atlas -- 3 horses
:Saturn I -- 20 horses
:Proton-K -- 44 horses
:Atlas-Centaur -- 8 centaurs
:Titan IIIA -- 7 horses
:Saturn IB -- 45 horses
:Soyuz -- 14 horses
:Saturn V -- 262 horses
:Black Arrow -- <1 horse (4 dogs)
:N1 -- 211 horse -- Exploded on Launch pad
:Long March 1 -- 2 horses
:N-I (Japan) -- 4 horses
:Delta 0900 -- 3 horses
:Ariane 1 -- 3 horses
:SLV (India) -- <1 horse (1 dog)
:N-II -- 4 horses
:1981 Oldsmobile -- 4 horses
:ASLV -- <1 horse (4 dogs)
:Long March 4A -- 9 horses
:Ariane 4 -- 16 horses
:Shavit (Israel) -- <1 horse (6 dogs)
:Energia -- 218 horses
:Pegasus -- 1 Pegasus
:Atlas I -- 13 horses
:PSLV -- 8 horses
:J-I -- 2 horses
:Long March 3B -- 27 horses
:H-IIA -- 22 horses
:Delta IV-H -- 64 horses
:Falcon 1 -- 1 horse
:Ariane 5ES -- 47 horses
:H-IIB -- 37 horses
:Unha (North Korea) -- <1 horse (2 dogs)
:Atlas V 541 -- 38 horses
:Falcon 9 -- 29 horses
:Antares -- 14 horses
:Stratolaunch -- 14 horses
:Falcon Heavy -- 118 horses
:SLS Block 1 -- 156 horses
:SLS Block 1B -- 217 horses
:SLS Block 2 -- 289 horses

:[The timeline:]
:1950s, 1960s, 1970s, 1980s, 1990s, 2000s, Future

A larger transcript with image descriptions can be found here: [[1461: Payloads/Transcript|Full transcript]]

==Trivia==
*Later after the initial release of this comic Randall added a link to this page. It's viewable in the HTML-source or here: [https://xkcd.com/1461/info.0.json https://xkcd.com/1461/info.0.json]. The text is: ''"This comic is an infographic. A very good transcription is available in complete form here: http:\n\nwww.explainxkcd.com\nwiki\nindex.php\n1461"''. At the time this was added here was no written transcript but a complete explain section.

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Large drawings]]
[[Category:Charts]]
[[Category:Timelines]]
[[Category:Animals]]
[[Category:Squirrels]]
[[Category:Space]]
[[Category:Space probes]]
[[Category:Telescopes]]
[[Category:Mars rovers]]

1462: Blind Trials

2022-05-26T19:34:59Z

Green: Undoing vandalism

{{comic
| number = 1462
| date = December 19, 2014
| title = Blind Trials
| image = blind_trials.png
| titletext = Plus, you have to control for the fact that some people are into being blindfolded.
}}

==Explanation==
In research, a {{w|Blind Experiment|blind trial}} is an experiment where certain information about the test is concealed from the subjects and/or the testers, in order to reduce sources of bias in the results. A double-blind trial is one where neither the subject nor the testers know who has or has not received treatment (or for multiple treatments, which treatment).

A scientific approach also requires the use of {{w|control groups}} to determine the significance of observations in (clinical) trials. The members of the control group receive either no treatment or the "standard" treatment. However, to ensure "blindness" in the study, even if a control group is to receive no treatment, they must be given a {{w|placebo}}: an ineffective treatment given to ensure the doctors and/or patients are unaware whether they are being given the treatment.

For example, in clinical drug trials, when a treatment being tested is administered in the form of a pill, a visually-identical inert pill is given to the control group so no one will know if a subject has been given the treatment or a placebo. In pop culture, placebos in pill-form are often made of sugar, which has negligible medical effects.

Controls and blinding are crucial to distinguish the actual effects of the treatment from the {{w|placebo effect}}, or the psychologically-induced effects of a subject's belief that a treatment will or will not help them, which may have real physiologic effects or influence the reporting of subjective measures such as pain level or the presence of side effects. It is vital that there are no clues available to distinguish between the different groups. Even subtle cues from the body language of the testers are sufficient to trigger placebo effect, making double-blind trials necessary.

Challenges exist in designing placebo alternatives to certain physical treatments that might be tested, such as acupuncture; in this case the best quality trials have typically used either special 'joke' retractable needles that only give the illusion of proper penetration or the practitioner/researcher deliberately and safely avoids the traditional {{w|Meridian (Chinese medicine)|meridians}} on the body for the treatment concerned so that the patient remains 'blind' to their role in the trial. The practitioner must otherwise be consistent in treatment between groups and not be involved in the medical assessment phase for properly double-blinded conditions, where the most reliable results still seem to only show a significant placebo effect at work.

There are, however, certain cases where it is almost impossible to make the experience of the control group identical to that of the test group. Making a real and fake pill appear the same is a relatively trivial task, and the ignorance of participants to the details of a given established practice or procedure can allow for a certain level of blinding. However, it would be challenging (to say the least) to make the control group in the described experiment think that they are having lots of sex, when in fact they are not. The description of the control group as taking sugar pills is a laughably poor placebo substitute, as the pills themselves may affect cardiovascular health, therefore ruining the concept of a {{w|controlled experiment}}, especially if it is a double-blind trial, and nobody knows who got sugar and who got sex.

Scientific research involving humans is extremely challenging to conduct because of the difficulty in finding appropriate control groups. This is one of the reasons animal experiments (for instance involving inbred strains of mice) are so common.

The title text adds another twist by taking “blind” literally, and noting that for some people, being blindfolded increases their enjoyment of sexual activity, thereby acting as a confounding variable.

Despite this, it should be noted that Cardiovascular health is typically measured in terms of objective data such as cholesterol levels, ejection fraction, and morbidity/mortality data like the frequency of myocardial infractions, strokes, or sudden cardiac death. Even sighted, it would be difficult for either subjects or researchers to manipulate this kind of data.

==Transcript==
:[Megan is pointing at charts hanging on the wall.]
:Megan: We've designed a double-blind trial to test the effect of sexual activity on cardiovascular health.
:Both groups will ''think'' they're having lots of sex, but one group will actually be getting sugar pills.

:The limitations of blind trials

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Sex]]
[[Category:Psychology]]
[[Category:Science]]

1466: Phone Checking

2022-05-26T19:34:17Z

Green: Undoing vandalism

{{comic
| number = 1466
| date = December 29, 2014
| title = Phone Checking
| image = phone_checking.png
| titletext = 'Where were you when you learned you'd won?' 'I was actually asleep; I woke up when I refreshed the webite and saw the news.'
}}

==Explanation==
[[Cueball]] asks [[Megan]] what's up, and Megan announces that there's a Compulsive Phone Checking Championship, presumably an award for the person who checks their phone the most often. Megan checks her phone to see if the winner has been announced, but finds the site's server is {{w|server overload|overloaded}}, which would be exactly what would happen if many people were checking their phones simultaneously. Given the nature of the contest, we can presume this is indeed the case. As a solution, Megan tries refreshing repeatedly, sending more load to the server and, thus, making it unavailable longer.

This compulsive behavior predates the popularity of mobile phones as shown in [[477: Typewriter]] and [[862: Let Go]].

Another possible analysis is that the site was purposely down, and instead was the contest itself, to see how many times different users would refresh the page within a time period, or perhaps to the last one standing, determining the winner.

The title text implies that Megan checks her phone so compulsively she even does it in her sleep. This probably contributed to her victory. A "webite" is probably either a typo of "website" or a pinned tab in a web browser.

==Transcript==
:[Cueball approaching Megan.]
:Cueball: What's up?
:Megan: They're announcing the winner of the compulsive phone-checking championship.

:[Megan checks her phone.]

:[Megan puts her phone away.]

:[Megan checks her phone again.]
:Cueball: Did you win?
:Megan: Site's down.
:Cueball: Weird.
:Megan: I'll keep refreshing.

{{comic discussion}}

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

1467: Email

2022-05-26T19:32:42Z

Green: Undoing vandalism

{{comic
| number = 1467
| date = December 31, 2014
| title = Email
| image = email.png
| titletext = My New Year's resolution for 2014-54-12/30/14 Dec:12:1420001642 is to learn these stupid time formatting strings.
}}

==Explanation==
A [[:Category:New Year|New Year comic]], where [[Megan]] asks [[Beret Guy]] if he has any {{w|New Year's resolutions}}, and even though this is just before {{w|new year}} 2015, his resolution is to find out what an email is!

Despite being in popular use since 1998 when free email providers appeared and having existed since before 1982 when {{w|SMTP}} was established, Beret Guy apparently doesn't understand what {{w|email}} is, even though he maintains a web page that includes his email address. Megan wonders how else he expects electronic messages to be sent. She explains that one must check email regularly, making a slight at {{w|voicemail}}, which she implies is not worth ever checking.

Beret Guy offers two alternatives: {{w|Fax}} and {{w|Snapchat}}. Megan refers to Snapchat as "the naked pic thing", calling to mind how many of its users send naked pictures of themselves over the Internet. Beret Guy replies that people use fax machines for more than just "faxting" (a made-up term similar to {{w|sexting}}), implying that many people send sexual content via fax, a technology that predates SMTP by more than a century. Beret Guy knows what a fax is, which implies he is very behind in the technology world, so it makes sense he doesn't know what email is. But he also knows what Snapchat is, which was very popular around the time of this comic. Either Beret Guy heard about it in a similar way to email, or he definitely knows what it is and/or uses it. What's strange is that if Beret Guy knows what Snapchat is, he should know what email is as well, since you need to provide an email account in order to create a snapchat account.

The title text, which could be [[Randall]]'s New Year's resolution for 2015, refers to various date/time formats. In programming, a point in time (e.g. the current system time) is usually stored and processed as a single number that represents the count of seconds that have elapsed since a given starting time known as "epoch" (the Unix standard epoch is January 1, 1970 at midnight, {{w|UTC}}). In order to make sense to people, this number must be converted to a human-readable format, but programmers must choose a format that best meets the needs of their users. This can be a complicated problem to solve, given that there are many different standard formats for different regions, different levels of precision for different applications, and differences between "universal time" and a user's local time zone. Randall has previously advocated for widespread adoption of the {{w|ISO 8601}} format as a universal standard.

The title text also probably references a twitter outage that took place on December 29, which was blamed on an [http://www.theguardian.com/technology/2014/dec/29/twitter-2015-date-bug error in a date format string].

Most programming languages provide functions to create a custom date-format string using "tokens" that represent different parts of the date/time. Here, Randall appears to have used one of these functions with the string "%Y-%M-%D %h:%m:%s", which looks like it should produce a date and time as "Year-Month-Day Hour:Minute:Second". However, he used the wrong tokens for this:

*%Y = 4-digit year (2014)
*%M = minute (54)
*%D expands to %m/%d/%y, which is "month/day/2-digit year" in the user's local time zone rather than UTC. ("12/30/14" - see below)
*%h = abbreviated month name ("Dec")
*%m = 2-digit month (12)
*%s = Unix timestamp (1420001642 seconds since epoch)

The "%s" token shows us the actual {{w|Unix time|Unix timestamp}} used (1420001642), which corresponds to 2014-12-31 at 04:54:02 UTC. The format string shown above thus yields "2014-54-12/30/14 Dec:12:1420001642". Note that the middle portion of this string shows "12/30" instead of "12/31" - this is due to the %D token expressing the date in Randall's local time zone (Eastern Standard Time, or EST), which is 5 hours before UTC. The time there was 23:54:02, or just before midnight, on the previous day.

The correct format string for Randall's apparent desired result is "%Y-%m-%d %H:%M:%S", which gives the string "2014-12-31 04:54:02" (UTC) or "2014-12-30 23:54:02" (EST). Given the similarity between Randall's string and the correct one, it is easy to see how this type of formatting is confusing and often frustrating for programmers - particularly those not intimately familiar with these functions.

Randall previously addressed date/time formatting in [[1179: ISO 8601]] and [[1340: Unique Date]] (the latter of which uses a formatting string correctly).

This was the second comic in a row with Megan holding a smart phone, the first being [[1466: Phone Checking]]. The comic before that one was also about smart phones: [[1465: xkcd Phone 2]].

==Transcript==
:[Megan approaches Beret Guy.]
:Megan: Any New Year's resolutions?
:Beret Guy: Gonna figure out what email is.
:Megan: ''...Email?''

:[Megan points to her phone.]
:Beret Guy: People always say they're sending them. They sound really into it, so I always nod, but I have no idea what it is.
:Megan: You have an address on your website!

:[Megan and Beret Guy walking.]
:Beret Guy: Oh, ''that's'' what that thing is.
:Megan: Email is important! You can't just ''never'' check it. It's not like voicemail.

:Beret Guy: Can't they just send messages ''normally?''
:Megan: How?
:Beret Guy: Fax! Or Snapchat.
:Megan: ...The naked pic thing?
:Beret Guy: Fax machines aren't ''just'' for faxting!

==Trivia==
The Unix timestamp is a standard method of keeping time by counting the absolute number of seconds that have elapsed since a set point in time known as "epoch", defined as midnight on January 1, 1970, Coordinated Universal Time (UTC). Epoch, in {{w|ISO-8601}} format, is "1970-01-01T00:00:00Z", where Z indicates UTC.

The timestamp in this comic's title text (1420001642) is 1,420,001,642 seconds since epoch. The process of converting that number into a human-readable time is as follows:

*Years since 1970 = 1,420,001,642 seconds / 60 seconds per minute / 60 minutes per hour / 24 hours per day / 365.25 days per year
**This yields 44 years plus 31,467,242 seconds.
**The year for the timestamp is 1970 + 44 years = '''2014'''.
***Note: The year calculation specifies 365.25 days per year to account for {{w|leap year|leap years}} (every fourth year adds an extra day). Also note that 2014 is not a leap year.
*Days since start of year = 31,467,242 seconds / 60 seconds per minute / 60 minutes per hour / 24 hours per day
**This yields 364 days plus 17,642 seconds. Given January 1 is considered the ''first'' day of the year, this means we are on the 365th day of 2014.
**The 365th day of a non-leap year is '''December 31'''. December is the '''12th month''' in the Gregorian calendar.
*The remaining seconds can be converted into a time:
**Hours since start of day = 17,642 seconds / 60 seconds per minute / 60 minutes per hour = '''4 hours''' plus 3,242 seconds
**Minutes since start of hour = 3,242 seconds / 60 seconds per minute = '''54 minutes''' plus '''2 seconds'''

Thus, Randall's timestamp represents the time "'''2014-12-31'''T'''04:54:02'''Z" (again in ISO-8601 format).

{{comic discussion}}

[[Category:New Year]]
[[Category:Comics featuring Beret Guy]]
[[Category:Comics featuring Megan]]
[[Category:Email]]

1468: Worrying

2022-05-26T19:32:03Z

Green: Undoing vandalism

{{comic
| number = 1468
| date = January 2, 2015
| title = Worrying
| image = worrying.png
| titletext = If the breaking news is about an event at a hospital or a lab, move it all the way over to the right.
}}

==Explanation==
This chart is a visual representation of how worried people should be by various events in real life compared to the same events in movies, based on the likelihood of the event causing serious harm. In effect, it's poking fun at various cliches and the emphasis on dramatic flair, regardless of realism. The chart's Y-axis indicates how worrying an event is in real life (from "not very worried" to "very worried"), while its X-axis shows how worrying the event is in movies. Nine events are shown in the chart, all of them cliches in the medium of film:

*'''Spilling a drink on your shirt''': In both real life and in movies, this just causes a stain and maybe a little embarrassment.
*'''Nosebleed''': Nosebleeds are common in real life, as they can result from even a mild impact to the face, or even dried out sinuses. There are some conditions where nosebleeds can indicate something more serious (such as a stroke, or radiation poisoning), but those are vastly outnumbered by bleeds that are relatively harmless. Unless there's a reason to believe that a nosebleed is connected to something else, they rarely even require medical attention. {{tvtropes|DeadlyNosebleed|Nosebleeds in movies}} are almost always a sign that something ''is'' seriously wrong - the common, mundane nosebleeds almost never come up.
*'''Breaking news''': People in real life commonly don't pay much attention to the news at all, so many breaking stories go unnoticed until much later. Most breaking news stories are also about non-threatening events (e.g. presidential addresses) or events that are far removed from the viewer. However, in movies, "breaking news" broadcasts are almost always a means to introduce a significant plot element which directly impact the protagonists, and are usually very serious events. XKCD has referenced [[1387|news reports as foreshadowing before]].
*'''Parking ticket''': Tickets in movies are almost always ignored, but in real life, they are moderately worrying because they cost money and can tarnish your driving record.
*'''Persistent cough''': In real life, coughing fits can be a sign of serious illness, and are worth having checked out, but the large majority of them indicate only minor and common illnesses. In movies, just like with nosebleeds, a {{tvtropes|IncurableCoughOfDeath|persistent cough}} almost always indicates a potentially deadly disease.
*'''"We need to talk."''': This phrase is a common, stereotypical lead-in to a serious conversation, usually about a couple's relationship status. In real life, as in the movies, prefacing a conversation with that phrase indicate that something serious, and possibly very upsetting, is about to be discussed. such conversations are rarely deadly, but are often upsetting.
*'''Getting knocked out by a punch''': In movies, a character who is {{tvtropes|TapOnTheHead|knocked out by a punch}} always wakes up sometime later with no lasting effects, making it less cause for concern than a spilled drink. In real life, being rendered unconscious by a physical impact is extremely serious, it can result in a variety of permanent impacts, up to and including brain damage and even death.
*'''Chest wounds''': The chart mentions wounds on both your right and left sides. In real life, a chest wound to either side is extremely worrying. But in movies, getting wounded on the right side of the chest will rarely deal lasting damage to the hero or primary villain, to show how badass they are. Wounds on the ''left'' side of the chest generally signify swift death. This is likely due to the common misconception that the heart is on the left side of the chest - it is actually in the center, with a slight tendency to the left. However, even left-side chest wounds in movies are apparently still less worrisome than coughs and nosebleeds. It must also be noted that the term "chest wound" is broader than what the author of the comic appears to mean. More narrow terms of "thoracic gunshot wound", "gunshot chest wound", "thoracic ballistic trauma" or "penetrating chest wound" (the latter is slightly broader and includes the damage inflicted by blades and other impaled objects) would be more appropriate because just a "chest wound" includes such insignificant events as minor skin cuts in the chest area.

The title text expands on the aforementioned breaking news reports. While already overly worrying whenever they occur in movies compared to real life, should the movie's news report cover an event at a hospital (usually an outbreak of some major disease) or a laboratory (a monster escaping, a toxic gas released, an explosion, etc.), these events are universally much more worrisome than any other type of news story since they are guaranteed to be important for the protagonists in short order. In real life, breaking news from such locations may be more likely to be serious, but are still very unlikely to impact the viewer directly.

==Table==
The comic shows an X-Y plot of events, showing how worried you should be ''in real life'' on the vertical axis and ''in movies'' on the horizontal axis. The axis goes from "not very worried" to "very worried".

Below is a table listing the coordinates for each event according to how worrying it is. The coordinates have been found by measuring each dot to the two axises and then assuming that the extremes are at 100%.
*Note that this gives two possible ways to interpret the Y-axis "In real life" coordinate.
**Either chest wound is at 100% - this is the first Y-axis coordinate given below under "In real life".
**But alternatively it could be the most worrisome event overall that should be set to 100% including also the most worrisome event on the X-axis for "In movies". In this case, the nosebleed event sets the 100% bar higher, thus lowering the percentage for the "In real life" events. Either way could be argued, and thus this other coordinate is given as In Real Life vs. Nose Bleed ('''IRL vs. NB''').
*For the "In movies" coordinate nosebleed is at 100%. However, since nosebleed is located past the end of the x-axis arrow it could be argued that it is this event that is off the chart in the movies. But this table will assume this as the 100% mark either overall or at least for the X-axis for "In Movies".

{| class="wikitable sortable"
! In real life !! IRL vs. NB !! In movies !! Event
|-
| 100% || 73% || 30% || Chest wound on your right side
|-
| 100% || 73% || 80% || Chest wound on your left side
|-
| 81% || 59% || 9% || Getting knocked out by a punch
|-
| 75% || 55% || 62% || "We need to talk."
|-
| 51% || 37% || 90% || Persistent cough
|-
| 28% || 20% || 8% || Parking ticket
|-
| 24% || 18% || 74% || Breaking news
|-
| 12% || 8% || 11% || Spilling a drink on your shirt
|-
| 11% || 8% || 100% || Nosebleed
|}

==Transcript==
:'''How worried should you be when various things happen to you:'''
:[A chart with a scatter plot on which 9 dots are labeled. Each axis has a title and a scale. Reading from the top to the bottom and then left to right along the axis are:]
:Very worried
:'''...In Real Life'''
:Not very worried

:Not very worried
:'''...In Movies'''
:Very worried

:[The labels in the chart from the top:]
:[This first entry is standing in the middle of a square bracket that points to the two next entires both of which are at the same level:]
:Chest wound
:...on your right side
:...on your left side
:Getting knocked out by a punch
:"We need to talk."
:Persistent cough
:Parking ticket
:Breaking news
:Spilling a drink on your shirt
:Nosebleed

{{comic discussion}}

[[Category:Scatter plots]]
[[Category:Rankings]]

List of all comics (3000-3500)

2022-05-26T19:30:25Z

Green: Undoing vandalism

This is the list of comics from '''2501 to {{LATESTCOMIC}}'''.
:For the first 500 comics, see [[List of all comics (1-500)]].
:For comics 501-1000, see [[List of all comics (501-1000)]].
:For comics 1001-1500, see [[List of all comics (1001-1500)]].
:For comics 1501-2000, see [[List of all comics (1501-2000)]].
:For comics 2001-2500, see [[List of all comics (2001-2500)]].
: The whole list is available at [[List of all comics (full)]].

You may also see the list of comics in the order they appeared at the [https://xkcd.com/archive/ xkcd archive].

{| class="wikitable sortable plainlinks table-padding"
|-
!xkcd
!Title
!Talk
!Image
!Date<onlyinclude>
{{comicsrow|2624|2022-05-25|Voyager Wires|voyager wires.png}}
{{comicsrow|2623|2022-05-23|Goofs|goofs.png}}
{{comicsrow|2622|2022-05-20|Angular Diameter Turnaround|angular diameter turnaround.png}}
{{comicsrow|2621|2022-05-18|Mainly Known For|mainly known for.png}}
{{comicsrow|2620|2022-05-16|Health Data|health data.png}}
{{comicsrow|2619|2022-05-13|Crêpe|crepe.png}}
{{comicsrow|2618|2022-05-11|Selection Bias|selection bias.png}}
{{comicsrow|2617|2022-05-09|Maps|maps.png}}
{{comicsrow|2616|2022-05-06|Deep End|deep_end.png}}
{{comicsrow|2615|2022-05-04|Welcome Back|welcome_back.png}}
{{comicsrow|2614|2022-05-02|2|2.png}}
{{comicsrow|2613|2022-03-29|Bad Map Projection: Madagascator|bad map projection madagascator.png}}
{{comicsrow|2612|2022-04-27|Lightsabers|lightsabers.png}}
{{comicsrow|2611|2022-04-25|Cutest-Sounding Scientific Effects|cutest sounding scientific effects.png}}
{{comicsrow|2610|2022-04-22|Assigning Numbers|assigning numbers.png}}
{{comicsrow|2609|2022-04-20|Entwives|entwives.png}}
{{comicsrow|2608|2022-04-18|Family Reunion|family reunion.png}}
{{comicsrow|2607|2022-04-15|Geiger Counter|geiger counter.png}}
{{comicsrow|2606|2022-04-13|Weird Unicode Math Symbols|weird unicode math symbols.png}}
{{comicsrow|2605|2022-04-11|Taylor Series|taylor series.png}}
{{comicsrow|2604|2022-04-08|Frankenstein Captcha|frankenstein captcha.png}}
{{comicsrow|2603|2022-04-06|Childhood Toys|childhood toys.png}}
{{comicsrow|2602|2022-04-04|Linguistics Degree|linguistics degree.png}}
{{comicsrow|2601|2022-04-01|Instructions|instructions.png}}
{{comicsrow|2600|2022-03-30|Rejected Question Categories|rejected question categories.png}}
{{comicsrow|2599|2022-03-28|Spacecraft Debris Odds Ratio|spacecraft debris odds ratio.png}}
{{comicsrow|2598|2022-03-25|Graphic Designers|graphic designers.png}}
{{comicsrow|2597|2022-03-23|Salary Negotiation|salary negotiation.png}}
{{comicsrow|2596|2022-03-21|Galaxies|galaxies.png}}
{{comicsrow|2595|2022-03-18|Advanced Techniques|advanced techniques.png}}
{{comicsrow|2594|2022-03-16|Consensus Time|consensus time.png}}
{{comicsrow|2593|2022-03-14|Deviled Eggs|deviled eggs.png}}
{{comicsrow|2592|2022-03-11|False Dichotomy|false dichotomy.png}}
{{comicsrow|2591|2022-03-09|Qua|qua.png}}
{{comicsrow|2590|2022-03-07|I Shouldn't Complain|i shouldnt complain.png}}
{{comicsrow|2589|2022-03-04|Outlet Denier|outlet denier.png}}
{{comicsrow|2588|2022-03-02|Party Quadrants|party quadrants.png}}
{{comicsrow|2587|2022-02-28|For the Sake of Simplicity|for the sake of simplicity.png}}
{{comicsrow|2586|2022-02-25|Greek Letters|greek letters.png}}
{{comicsrow|2585|2022-02-23|Rounding|rounding.png}}
{{comicsrow|2584|2022-02-21|Headline Words|headline words.png}}
{{comicsrow|2583|2022-02-18|Chorded Keyboard|chorded keyboard.png}}
{{comicsrow|2582|2022-02-16|Data Trap|data trap.png}}
{{comicsrow|2581|2022-02-14|Health Stats|health stats.png}}
{{comicsrow|2580|2022-02-11|Rest and Fluids|rest and fluids.png}}
{{comicsrow|2579|2022-02-09|Tractor Beam|tractor beam.png}}
{{comicsrow|2578|2022-02-07|Sword Pull|sword pull.png}}
{{comicsrow|2577|2022-02-04|Sea Chase|sea chase.png}}
{{comicsrow|2576|2022-02-02|Control Group|control group.png}}
{{comicsrow|2575|2022-01-31|What If? 2|what if 2.png}}
{{comicsrow|2574|2022-01-28|Autoresponder|autoresponder.png}}
{{comicsrow|2573|2022-01-26|Alien Mission|alien mission.png}}
{{comicsrow|2572|2022-01-24|Alien Observers|alien observers.png}}
{{comicsrow|2571|2022-01-21|Hydraulic Analogy|hydraulic analogy.png}}
{{comicsrow|2570|2022-01-19|Captain Picard Tea Order|captain picard tea order.png}}
{{comicsrow|2569|2022-01-17|Hypothesis Generation|hypothesis generation.png}}
{{comicsrow|2568|2022-01-14|Spinthariscope|spinthariscope.png}}
{{comicsrow|2567|2022-01-12|Language Development|language development.png}}
{{comicsrow|2566|2022-01-10|Decorative Constants|decorative constants.png}}
{{comicsrow|2565|2022-01-07|Latency|latency.png}}
{{comicsrow|2564|2022-01-05|Sunshield|sunshield.png}}
{{comicsrow|2563|2022-01-03|Throat and Nasal Passages|throat and nasal passages.png}}
{{comicsrow|2562|2021-12-31|Formatting Meeting|formatting meeting.png}}
{{comicsrow|2561|2021-12-29|Moonfall|moonfall.png}}
{{comicsrow|2560|2021-12-27|Confounding Variables|confounding variables.png}}
{{comicsrow|2559|2021-12-24|December 25th Launch|december 25th launch.png}}
{{comicsrow|2558|2021-12-22|Rapid Test Results|rapid test results.png}}
{{comicsrow|2557|2021-12-20|Immunity|immunity.png}}
{{comicsrow|2556|2021-12-17|Turing Complete|turing complete.png}}
{{comicsrow|2555|2021-12-15|Notifications|notifications.png}}
{{comicsrow|2554|2021-12-13|Gift Exchange|gift exchange.png}}
{{comicsrow|2553|2021-12-10|Incident Report|incident report.png}}
{{comicsrow|2552|2021-12-08|The Last Molecule|the last molecule.png}}
{{comicsrow|2551|2021-12-06|Debunking|debunking.png}}
{{comicsrow|2550|2021-12-03|Webb|webb.png}}
{{comicsrow|2549|2021-12-01|Edge Cake|edge cake.png}}
{{comicsrow|2548|2021-11-29|Awful People|awful people.png}}
{{comicsrow|2547|2021-11-26|Siren|siren.png}}
{{comicsrow|2546|2021-11-24|Fiction vs Nonfiction|fiction vs nonfiction.png}}
{{comicsrow|2545|2021-11-22|Bayes' Theorem|bayes theorem.png}}
{{comicsrow|2544|2021-11-19|Heart-Stopping Texts|heart stopping texts.png}}
{{comicsrow|2543|2021-11-17|Never Told Anyone|never told anyone.png}}
{{comicsrow|2542|2021-11-15|Daylight Calendar|daylight calendar.png}}
{{comicsrow|2541|2021-11-12|Occam|occam.png}}
{{comicsrow|2540|2021-11-10|TTSLTSWBD|ttsltswbd.png}}
{{comicsrow|2539|2021-11-08|Flinch|flinch.png}}
{{comicsrow|2538|2021-11-05|Snack|snack.png}}
{{comicsrow|2537|2021-11-03|Painbow Award|painbow award.png}}
{{comicsrow|2536|2021-11-01|Wirecutter|wirecutter.png}}
{{comicsrow|2535|2021-10-29|Common Cold Viruses|common cold viruses.png}}
{{comicsrow|2534|2021-10-27|Retractable Rocket|retractable rocket.png}}
{{comicsrow|2533|2021-10-25|Slope Hypothesis Testing|slope hypothesis testing.png}}
{{comicsrow|2532|2021-10-22|Censored Vaccine Card|censored vaccine card.png}}
{{comicsrow|2531|2021-10-20|Dark Arts|dark arts.png}}
{{comicsrow|2530|2021-10-18|Clinical Trials|clinical trials.png}}
{{comicsrow|2529|2021-10-15|Unsolved Math Problems|unsolved math problems.png}}
{{comicsrow|2528|2021-10-13|Flag Map Sabotage|flag map sabotage.png}}
{{comicsrow|2527|2021-10-11|New Nobel Prizes|new nobel prizes.png}}
{{comicsrow|2526|2021-10-08|TSP vs TBSP|tsp vs tbsp.png}}
{{comicsrow|2525|2021-10-06|Air Travel Packing List|air travel packing list.png}}
{{comicsrow|2524|2021-10-04|Comet Visitor|comet visitor.png}}
{{comicsrow|2523|2021-10-01|Endangered|endangered.png}}
{{comicsrow|2522|2021-09-29|Two-Factor Security Key|two factor security key.png}}
{{comicsrow|2521|2021-09-27|Toothpaste|toothpaste.png}}
{{comicsrow|2520|2021-09-24|Symbols|symbols.png}}
{{comicsrow|2519|2021-09-22|Sloped Border|sloped border.png}}
{{comicsrow|2518|2021-09-20|Lumpers and Splitters|lumpers and splitters.png}}
{{comicsrow|2517|2021-09-17|Rover Replies|rover replies.png}}
{{comicsrow|2516|2021-09-15|Hubble Tension|hubble tension.png}}
{{comicsrow|2515|2021-09-13|Vaccine Research|vaccine research.png}}
{{comicsrow|2514|2021-09-10|Lab Equipment|lab equipment.png}}
{{comicsrow|2513|2021-09-08|Saturn Hexagon|saturn hexagon.png}}
{{comicsrow|2512|2021-09-06|Revelation|revelation.png}}
{{comicsrow|2511|2021-09-03|Recreate the Conditions|recreate the conditions.png}}
{{comicsrow|2510|2021-09-01|Modern Tools|modern tools.png}}
{{comicsrow|2509|2021-08-30|Useful Geometry Formulas|useful geometry formulas.png}}
{{comicsrow|2508|2021-08-27|Circumappendiceal Somectomy|circumappendiceal somectomy.png}}
{{comicsrow|2507|2021-08-25|USV-C|usv c.png}}
{{comicsrow|2506|2021-08-23|Projecting|projecting.png}}
{{comicsrow|2505|2021-08-20|News Story Reaction|news story reaction.png}}
{{comicsrow|2504|2021-08-18|Fissile Raspberry Isotopes|fissile raspberry isotopes 2x.png}}
{{comicsrow|2503|2021-08-16|Memo Spike Connector|memo spike connector.png}}
{{comicsrow|2502|2021-08-13|Every Data Table|every data table.png}}
{{comicsrow|2501|2021-08-11|Average Familiarity|average familiarity.png}}</onlyinclude>
|}

[[Category:Comics| ]]