explain xkcd - User contributions [en]

2549: Edge Cake

2025-10-08T16:59:13Z

82.132.237.234: /* Explanation */

{{comic
| number = 2549
| date = December 1, 2021
| title = Edge Cake
| image = edge_cake.png
| titletext = Every time IERS adds or removes a leap second, they send me a birthday cake out of superstition.
}}

==Explanation==
[[Megan]] — possibly an {{w|IERS}} (International Earth Rotation and Reference Systems) agent — wishes Emily, represented as [[Hairbun]], Happy Birthday. This prompts a confused [[Cueball]] to ask if her birthday was sometime last month. Emily explains that she was born over the North Pole in a plane, meaning that she was born in every timezone at once. Technically though this is false, as there are some timezones (such as {{w|Nepal Standard Time|UTC+5:45}}) that are not represented at the north pole. Except for the one hour before it is midnight at the International Date Line, the date in eastern time zones is one day ahead of western time zones, so Emily would have been born on two days at once.

She also says that it was February 29 (presumably it was also February 28 or March 1 in some time zones). February 29 only happens at most once every four years in the Gregorian calendar, adding to the confusion — people born on February 29 often celebrate their non-leap-year birthdays on arbitrary days (or {{w|The Pirates of Penzance#Synopsis|not at all}}). Normally {{w|Birth aboard aircraft and ships|one could simply use the time zone of the city the airplane took off from}}, but the airline company was changing ownership from one country to another at the time, so this option has apparently been ruled out. This is not terribly logical, however, since contracts transferring ownership usually specify an exact time (commonly one minute before or after midnight in a specific time zone to avoid confusion on which day midnight is in) to come into effect. Regardless of which time zone(s) she was in when she was born this is an absolute time and if she was born before it she would have been born in an aircraft of the first country and if after it in an aircraft of the second country. Alternately, the time zone of the city the aircraft took off from doesn't change even if the nationality of the plane changes in midair, so that should have still been an option.

The punchline is that rather than try to identify the correct birthday for Emily, the {{w|BIPM}} has decided to let her have birthdays whenever she wants. This doesn't make much sense, however. As noted above even if she was born in every time zone at once it could only have been on one of two days (February 29, plus either February 28 or March 1). Since it is common for people born on February 29 to celebrate on February 28 in non-leap years, it would have been trivial to pick the non-leap day present in some of the time zones (either February 28 or March 1) and declare it Emily's birthday. It is possible that Emily was told, "You can choose when you want your birthday to be", and Emily decided to exploit the lack of specificity to the degree presented in the comic.

In real life researchers in the Arctic at or near the North Pole use {{w|Coordinated Universal Time}} as the [http://www.thoughtco.com/the-north-pole-1435098 local time standard] by convention, to avoid this exact problem. Thus it could have been said that Emily was born on the date that it was at that time in UTC. Furthermore, it is extremely unlikely that she would have been born at the exact instant the plane was over the north pole, indeed, it is unlikely that the plane even traveled over the exact pole, as opposed to a few miles or even feet to either side of it. With modern positioning equipment such as GPS, it should have been possible to determine which time zone the plane was in when she was born. Even in the impossibly unlikely event that she was directly above the pole at the instant of her birth, at jetliner speeds the plane was traveling about ten miles per minute, so a reasonable delay of even seconds in declaring "time of birth" would have placed the plane and her clearly in one time zone.

Both the comic title and Cueball's final line are puns on "{{w|edge case}}", an engineering term referring to situations or conditions that are unusual in a way likely to cause problems unless specifically accounted for. Edge pieces are generally only important with sheet goods (brownies, sheet cakes, etc), which are typically cut into pieces creating a difference between pieces originating on the edge and pieces originating from the center. Since the top and sides of a cake are often frosted, an edge piece has two faces covered in frosting and a corner piece has three, while a center piece only has one. Depending upon your relative preferences between the surface (often icing over marzipan) and core body of the cake (which can be fruitcake, or some variety of spongecake, etc., but not actually obvious which until the cake is cut), it being an edge-faced slice can be considered a bonus. Cueball certainly seems to appreciate this.

The title text states that the {{w|IERS}} sends Emily a cake every time they add or remove a leap second, out of superstition (perhaps Megan is delivering that cake). The International Earth Rotation and Reference Systems Service is in charge of global time standards. It occasionally adds one leap-second to {{w|Coordinated Universal Time}} to adjust for changes in the rotation speed of the Earth.

The comic might also be a modern version of the ''{{w|SS Warrimoo}}'', a passenger liner that reportedly crossed the international date line at the equator on midnight December 31, 1899. This would have placed her bow in the Southern Hemisphere on January 1, 1900, her stern in the Northern Hemisphere on December 31, 1899. She would therefore have been simultaneously in two different hemispheres, on two different days, in two different months, in two different years and in two different decades. By {{w|Century#Start and end of centuries|some definitions}}, possibly also in two different centuries, though this precludes being in two different ''seasons'', by all {{w|Winter#Meteorological reckoning|common}} {{w|Winter#Astronomical and other calendar-based reckoning|variations}} of their definition.

==Transcript==
:[Megan is walking towards Cueball and Emily (who resembles Hairbun), holding a cake.]
:Megan: Happy birthday, Emily!
:Cueball: Wait, wasn't that last month? When's your birthday, anyway?
:Emily: It's complicated.

:[A diagram of a flight path over the North Pole, with meridian lines radiating out from the center. Emily's dialogue appears above the diagram, but she herself does not appear in this panel.]
:Emily: My mom went into labor on an arctic international flight that diverted directly over the North Pole.
:Emily: I was born in every time zone at once.

:[With Megan standing behind her, Emily holds out a plate of cake to Cueball.]
:Emily: It was also February 29th, and the airline was just changing ownership between countries.
:Emily: The International Bureau of Weights and Measures finally issued a declaration that it's my birthday whenever I want.
:Emily: Cake?
:Cueball: Nice, it's all edge pieces.

==Trivia==
*Hairbun was last named "Emily" in [[788: The Carriage]].
**More specifically, that version of Hairbun represented {{w|Emily Dickinson}}, a real, historical person who had no such issues regarding her birthday.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Hairbun]]
[[Category:Aviation]]
[[Category:Time]]
[[Category:Engineering]]
[[Category:Science]]

1849: Decades

2025-10-08T16:52:22Z

82.132.237.234:

{{comic
| number = 1849
| date = June 12, 2017
| title = Decades
| image = decades.png
| titletext = In the 90s, our variety radio station used the tagline "the best music of the 70s, 80s, and 90s." After 2000, they switched to "the best music of the 80s, 90s, and today." I figured they'd change again in 2010, but it's 2017 and they're still saying "80s, 90s, and today." I hope radio survives long enough for us to find out how they deal with the 2020s.
}}

==Explanation==
{{incomplete|Figure out what radio station Randall was talking about in the title text and mention what it does now.}}
From the 1960s to the 1990s, it was common to group eras by decades. Fashion, music, and other cultural trends that changed relatively quickly were often defined by those decades. People casually and commonly referred to "the sixties", and so on, to separate these periods.

This pattern broke down after 1999, because it didn't naturally lend itself to an analogous phrase for the year from 2000-2009. A number of different terms have been proposed and used: "the {{w|Aughts}}", and "[https://www.bbc.co.uk/news/newsbeat-66199129 the noughties]" had been used for 1900-1909, but have an archaic flavor that may not work for everyone. "The {{w|2000s}}" and "the millenium" are ambiguous and clunky. None of these terms ever became popular enough to become a consensus term. Similarly for the period from 2010-2019, terms like "the 2010s" and "the teens" have been used, but not widely accepted.

The practical upshot of all of this is that verbally splitting time periods into clear decades simply became less obvious for the periods since 2000. While people still refer to earlier time periods by decades, it is far less common to do so when referring to recent years. The roll-over text gives the example that we still refer to "music of the '80s and '90s" (although the comic omits the apostrophes that might normally indicate the missing century digits), but rarely refer to "music of the 2000s" or something similar.

The time-line in the comic stretches into the future (as of the time of publication), and uses question marks to present uncertainty over whether the decade-grouping trend will return in the 2020s. On the one hand, such was a well-established custom, and we once again have clear language for it. On the other hand, after largely abandoning the custom for 20 years, it is far from certain that people will adopt it again.

What isn't mentioned in the comic, but may be relevant, is that, in the absence of those decade categories, it has become more common to refer to time periods and the people who grew up in them by somewhat arbitrary generational categories: Baby Boomers, Generation X, Millennials, Gen Z, and so on. This has provided an adequate substitute, since youth culture in the 2000s and 2010s has been more commonly defined as "{{w|Millennials#Cultural_identity|millennial culture}}". There are drawbacks to this (both because the terms are more loosely defined, and because they often come with negative connotations), but these trends may have become sufficiently ingrained that they could displace the older decade-based divisions.

The title text gives the specific example of [[Randall]]'s local radio station dividing music by decades, and points out they simply started talking around the decades from 2000 to 2019. He implies that whether they resume this pattern in the 2020s will be a good indicator of whether this speech pattern will resume, but expressed doubt whether radio will last long enough to find out. This is a jab at the radio industry, which has been in decline for a long time as it has faced increasing competition from other communications technologies. While it is unlikely that the radio industry will cease to exist in the near future, further decline seems probable.

In the title text, he refers to his radio station changing taglines. The station is most likely referring to "Mix 104.1" as [https://radiodiscussions.com/threads/80s-gone-from-wbmx.592448/ this forum] recounts both the original and second tagline.

Twenties were discussed again later in [[2249: I Love the 20s]].

==Transcript==
:[A timeline across the top of the box marks decades from 1960 to 2030, the labels are above the line and the ticks marking each decade are below.]

:[Label: 1960]
:60s Music; 60s Fashion; 60s Movies; 60s Culture

:[Label: 1970]
:70s Music; 70s Fashion; 70s Movies; 70s Culture

:[Label: 1980]
:80s Music; 80s Fashion; 80s Movies; 80s Culture

:[Label: 1990]
:90s Music; 90s Fashion; 90s Movies; 90s Culture

:[Label: 2000 and 2010]
:[Items grouped over two decades.]
:Fashion; Culture; Music; Movies

:[Label: 2020]
:[The text is in light grey font.]
:20s Music?; 20s Fashion?; 20s Movies?; 20s Culture?

:[Label: 2030]

:[Caption below the panel:]
:It's weird how for 20 years we stopped grouping our cultural memories by decade because "2000s" is ambiguous and and "Aughts" and "Teens" never really stuck.

==Trivia==
* Randall has by mistake written "and and aughts" in the caption for this comic, instead of "and aughts".

{{comic discussion}}

[[Category:Timelines]]
[[Category:Time]]
[[Category:Music]]
[[Category:Language]]

1394: Superm*n

2025-10-08T16:47:28Z

82.132.237.234: /* Explanation */

{{comic
| number = 1394
| date = July 14, 2014
| title = Superm*n
| image = superm_n.png
| titletext = See also: Spider-Man reboot in which he can produce several inches of web, doesn't need as much chalk powder on his hands when he goes rock climbing, and occasionally feels vaguely uneasy about situations.
}}

==Explanation==
By depicting how unimpressive the superhero {{w|Superman}} would be if his increase in powers, when compared to humans, were the same as the Moon's increase in apparent size during a {{w|supermoon}}, Randall points that the use of the term supermoon is an exaggeration. This comic was released two days after such a supermoon and there was a hype in 2014 because there were [https://science.nasa.gov/science-news/science-at-nasa/2014/10jul_supermoons three supermoons in a row] as NASA said.

A supermoon is an informal astronomical event where a full moon occurs when it is closest to Earth, causing the Moon to appear 10% brighter and about 7% larger than the '''average''' full moon appears. This is due to the {{w|apsidal precession}} of the Moon's {{w|elliptic orbit}} which has an {{w|orbital eccentricity}} of about 0.0549. The conditions for a supermoon happen once every 411 days, and the loose definition of the term means that the supermoon lasts for about two or three full moons.

Returning to the not-so-Superman, the average American adult man is 69 inches (175 cm) tall, with a {{w|standard deviation}} of 2.9 inches (7,4 cm). Not-so-Superman, at an assumed 74 inches (188 cm) tall, is within the 94th percentile — certainly a tall man, but by no means phenomenal. Basketball players, by way of example, are often more than 80 inches (203 cm) tall. "7% stronger" (most likely a reference to how the supermoon is 7% larger) is a bit harder to quantify, but it communicates "not actually impressive" to the reader all the same. For example, if an average man can lift 50 kg, the not-so-Superman would lift 53.5 kg.

The comic's title makes use of an asterisk that is being used as a wildcard. When using search queries an asterisk represents one or more characters. Therefore, Superm*n can represent the strings "Superman" and "Supermoon", as well as "Supermen", "Supermoan" and "Supermax prison".

The title text makes this same comparison with {{w|Spider-Man}}. Spider-Man is capable of firing large amounts of webbing, can cling to surfaces with superhuman gripping abilities, and has a sixth sense, "spider sense", that warns him about impending danger. The title text describes trivially minimal versions of these powers, analogous to the trivial size and brightness difference between a "supermoon" and a normal full moon. This also shows a much more accurate depiction of an actual spider's abilities, where they can produce several inches of a thin web, not the unrealistic amounts depicted in use by Spider-Man (usually by technical means, though occasionally [https://screenrant.com/tobey-maguire-spiderman-organic-webshooters/ organically]).

Supermoon is also referenced in [[1052: Every Major's Terrible#Verse 3|panel 25]] of [[1052: Every Major's Terrible]] and shortly thereafter in [[1080: Visual Field]], in both cases displaying the same distaste for the formulation, although not as clearly as here. Since then other comics have referred to the term, see this [[:Category:Supermoon|list]].

==Transcript==
:[Cueball is reaching for an item on a high shelf. Superman is rushing towards him.]
:Superman: I'll get it! I'm 5 inches taller and 7% stronger than the average man!

:[Caption below the panel:]
:The new supermoon-inspired '''''Superman''''' reboot

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Comics featuring Cueball]]
[[Category:Supermoon]]

Talk:2549: Edge Cake

2025-10-08T16:38:56Z

82.132.237.234: Originally mentioned "spring solstice", at one stage of composing, of course... Incompletely edited it when I cut it back... ;)

The cake being all edges is a reference to everything about her birth being an edge case.
[[Special:Contributions/172.70.110.227|172.70.110.227]] 03:41, 2 December 2021 (UTC)
: It seems likely that the title of the comic is a related pun: her birthday is an edge case, and so she has an edge cake.[[Special:Contributions/162.158.106.221|162.158.106.221]] 04:22, 2 December 2021 (UTC)
So is Hairbun officially named Emily now, sort of like how all instances of Megan are Megan even though she's only called that once? I know all the names here are just placeholders of convenience, but even then I've never know what the rules for naming are. [[User:Captain Video|Captain Video]] ([[User talk:Captain Video|talk]]) 06:11, 2 December 2021 (UTC)
: Well, Megan is referred to multiple times in the xkcds as "Megan", while the one time Hairbun was called Emily, it referred to the real{{citation needed}} Emily Dickinson. So, probably not. [[User:Bubblegum|bubblegum]]-[[User_talk:Bubblegum|talk]]|[[Special:Contributions/Bubblegum|contribs]] 02:44, 3 December 2021 (UTC)

Edge pieces on cake are often sought after because they hold more frosting, for cakes which are frosted while out of the pan. [[Special:Contributions/172.70.134.23|172.70.134.23]] 06:37, 2 December 2021 (UTC)
: I have an impression that Cueball is delighted by having only edge pieces, however some cakes edge pieces may be either sought for or avoided, depending on one's tastes. E.g. tarts have more crispy base cake content and less filling at the edges. One person may go for the filling, another for the crispy base. -- [[Special:Contributions/162.158.102.11|162.158.102.11]] 09:50, 2 December 2021 (UTC)

So it seems the events in the comic happened on Apr 1., as the "last month" birthday could be either Feb 28. or 29. -- [[Special:Contributions/162.158.102.11|162.158.102.11]] 09:50, 2 December 2021 (UTC)
:Not necessarily. Remember, Emily can have her birthday ''whenever she wants'', so the date this comic is set as is entirely arbitrary. [[Special:Contributions/172.70.178.51|172.70.178.51]] 12:26, 2 December 2021 (UTC)

Are there any particular existing arctic international flights that could have been the one Emily was born on? -- [[Special:Contributions/256.256.256.256|256.256.256.256]] 15:51, 2 December 2021 (UTC)
:There are a few possibities (at least pre-COVID, and obviously we'd be looking historically in this case anyway) as [https://interestingengineering.com/polar-routes-flights-that-go-over-earths-poles might be shown here]. There's two possible (but neither definite) International Datelines on the comic diagram, in case they help orient which from/to directions might have been diverted further in or out of their own kinks in the flightpath to coincide with 90°N. [[Special:Contributions/172.70.162.77|172.70.162.77]] 16:21, 2 December 2021 (UTC)

Expanded copies of this comic have been appearing on other comics, so large that it fills the whole screen for me. Is anyone else having this problem? [[User:Sarah the Pie(yes, the food)|Sarah the Pie(yes, the food)]] ([[User talk:Sarah the Pie(yes, the food)|talk]]) 22:24, 2 December 2021 (UTC)
:Someone (check the [[Special:RecentChanges|Recent Changes]] page, if you want) has been vandalising a lot of things. Currently I see a picture of an amphibious avian creature on this article's top (if I still need to revert it myself, I will do, but I've seen others have already been reverting other recent vandalism, so I may not need to by the time I've checked again). This very clever individual is obiviously mentally superior to us all(!) the way they can edit wiki pages seemingly at will... Impressive, eh? At some point I'm sure we'll get back to normlal, however boring that may be. [[Special:Contributions/172.70.90.67|172.70.90.67]] 23:33, 2 December 2021 (UTC)

Not to be too pedantic but isn't rotation a FREQUENCY, not a SPEED? [[User:Skulker|Skulker]] ([[User talk:Skulker|talk]]) 03:19, 3 December 2021 (UTC)
:Depends on the context (and scale). The convention is usually speed for rotation (surface(distance/time) when it's relevant, angular(revolutions/time) otherwise) to avoid conflicts with wave frequency (which is independent of speed). Also they can be freely converted, though converting to and from surface speed requires an additional radius term. The exception is, if comparing periodicity, sometimes frequency is used when it has special relevance (Ex: resonance) -- [[Special:Contributions/172.69.68.200|172.69.68.200]] 02:59, 4 December 2021 (UTC)

Tempted to add a link in the Trivia section to the [https://en.wikipedia.org/wiki/SS_Warrimoo Wikipedia] or [https://www.snopes.com/fact-check/ss-warrimoo/ Snopes] pages on the SS Warrimoo, a ship that (reportedly) was on the intersection of the Equator and the International Date Line at the stroke of midnight on January 1, 1900, with a number of interesting implications that follow. There's no way to prove that it actually happened, but it's fun to imagine and is somewhat similar to the premise of the comic. [[User:MeZimm|MeZimm]] ([[User talk:MeZimm|talk]]) 14:33, 3 December 2021 (UTC)
:What convinces me that it's a post-constructed yarn, rather than a legitimate account of a plausible event, is that the 1899-1900 'specialness' is (numerically aside) significant only from a more modern viewpoint. The dominant view at the alleged time of the incident, was the 1-rooted changeover between Centuries (1801 through to the end of 1900, then 1901-2000 to follow), and only changed as the more classical form of education/opinion phased out of common use. It was either later contrived from whole cloth as a tall-tale (if done at the time, it would have been given a 1900/1901 timestamp) or gradually embroidered with all the extra coincidental boundary-crossings (spatial and temporal) well after the actual inspirational seed incident in order to make a better anecdote/shaggy-dog-story.... [[Special:Contributions/172.70.86.12|172.70.86.12]] 15:33, 9 December 2021 (UTC)
:::Okay... but it's fun to imagine... and is somewhat similar to the premise of the comic. And I'd say it's a good deal more plausible than the situation presented in the comic. [[User:MeZimm|MeZimm]] ([[User talk:MeZimm|talk]]) 16:30, 14 December 2021 (UTC)

Many airplanes actually have limitations written into their operating manuals that prohibit flying north of 89 deg. N or south of 89 deg. S, mostly just so that the navigation software doesn't have to deal with the singularity. [[Special:Contributions/172.69.71.187|172.69.71.187]] 23:48, 3 December 2021 (UTC)
:bloody lazy engineers! [[Special:Contributions/108.162.219.107|108.162.219.107]] 12:19, 5 December 2021 (UTC)

Is it not possible that Emily's birth happened to occur at the same moment that the contract specified transfer of ownership? Additionally, is it not possible that the airplane took off from within UTC+13:00 or UTC+14:00 and that the moment of Emily's birth happened to occur in the brief one-or-two hour period in which it was March 1st at that airport, but February 28th in UTC-12:00? UTC-11:00 is inhabited, so it would be possible that ownership of an airplane that took off from within UTC+14:00 was transferred to a company based out of UTC-11:00 during the one-hour period that it was February 28th in UTC-11:00 and March 1st in UTC+14:00 and that, at that exact moment, it was passing over the North Pole. [[User:DL Draco Rex|DL Draco Rex]] ([[User talk:DL Draco Rex|talk]])

Am I alone in thinking that babies don't get born instantaneously? I've never given birth myself but i'd always got the impression that it's a process and any attempt to pick a precise 'instant' is going to be somewhat arbitrary. This means that the plane will very probably have travelled through a variety of time zones any of which could be the 'real' time of birth. [[Special:Contributions/172.70.85.155|172.70.85.155]] 05:29, 4 December 2021 (UTC)
:Time of birth is an arbitrary decision made by the midwives filling out forms in a hospital. The more unlikely point about that is that she'd be able to correlate the precise position of the plane at the exact time listed. [[Special:Contributions/108.162.219.187|108.162.219.187]] 12:37, 5 December 2021 (UTC)

Dickenson looks like a typo. Dickinson? [[Special:Contributions/172.70.162.77|172.70.162.77]] 08:44, 4 December 2021 (UTC)

Isn't an "all edge pieces cake" just a plate of cupcakes lol? [[User:Zman350x|Zman350x]] ([[User talk:Zman350x|talk]]) 06:46, 5 December 2021 (UTC)
:Only if you frosted all sides of it.[[Special:Contributions/172.70.114.3|172.70.114.3]] 12:25, 5 December 2021 (UTC)
:Alton Brown made a similar argument, but after experimenting, I strongly disagree. As with brownies, the cooking pattern is slightly different between having more edges and having a cupcake shape. In an edge piece, the edges and the corners are crisp while the center is gooey. Meanwhile, if cooked in a cupcake tin, while there might be more crispness, there is significantly less gooeyness. [[User:Cwallenpoole|Cwallenpoole]] ([[User talk:Cwallenpoole|talk]]) 14:23, 6 December 2021 (UTC)
:If you cut the sheet into quarters or if the whole was round and cut with radial slices there won't be any center piece(s). And there are more, unusual cuts that could result in all edge pieces...[[Special:Contributions/172.70.34.165|172.70.34.165]] 14:40, 6 December 2021 (UTC)
:My take was that a normal cake was baked, frosted and cut (with both edge and center pieces), and only the edge pieces were delivered to Emily.
::Only a cake baked in a fractal pan would be good enough for her!

Any commentary on the fact that the middle panel shows 25 time zones? [[User:Inca hoots|Inca hoots]] ([[User talk:Inca hoots|talk]]) 16:12, 9 December 2021 (UTC)

this comic has the same number as the carrier pigeon RFC, 2549. maybe related? [[Special:Contributions/172.70.114.251|172.70.114.251]] 19:37, 31 March 2022 (UTC)Bumpf

An edit was made to comment out the "two different decades" aspect, with inline explanation:
this is wrong: the turn of a decade always happens between YYY0 and YYY1, the same as for centuries and millennia
But it is not wrong. Ordinality does not generally apply in this case. Yes, if we describe any period as the "Nth decade/century/millenium", the 'correct' system starts at an appropriate 1-mark (as "Nth year" does) and goes to a 10-/100-/1000-mark which precedes the next "...and 1"-mark. But beyond the first century CE, or so, such an ordinal decadality tails off from practical use. 
A decade would normally be described as "the 1890s", not "the 190th decade", so anything that's "189_" is in the 19thC's century's '90s. Everything "190_" is a new decade (the "oh"s, or whatever variation it would be called), ''mostly'' in the 20thC, under the interpretation applied to the century (the 1-based one) by that editor's standards. "The 1900s" would be non-ordinal description of either the decade (190_ years) or century (19__ years), which perhaps context makes clear. In that respect, however, the former is entirely within the latter. 
I also redid the seasonal thing. Most meteorological "winter months" groupings have the whole of December lumped in with January and February (or summer months, for those south of the equator). Actual equinoxial season changes would switch either on or within a couple of days of 21/Dec (and {{w|Quarter days|any that treat}} "midwinter solstice" as truly ''mid''winter, and likewise with summer, are adrift by about 1.5 months). No other traditional season-markers, perhaps originally either astronomically or meteorologically inspired but with historic drift, seems to be using the modern 31Dec/1Jan point as a boundary. Though historically it has been true that years ticked over at the change of a season, that was often the different interpretation of the year (e.g. the one in which '''Dec'''ember was the '''ten'''th of the twelve months), held over (in Western calendars) only as some of the {{w|fiscal year}) variations that don't align to calendar years. [[Special:Contributions/82.132.237.234|82.132.237.234]] 16:34, 8 October 2025 (UTC)

Talk:2549: Edge Cake

2025-10-08T16:34:23Z

82.132.237.234:

The cake being all edges is a reference to everything about her birth being an edge case.
[[Special:Contributions/172.70.110.227|172.70.110.227]] 03:41, 2 December 2021 (UTC)
: It seems likely that the title of the comic is a related pun: her birthday is an edge case, and so she has an edge cake.[[Special:Contributions/162.158.106.221|162.158.106.221]] 04:22, 2 December 2021 (UTC)
So is Hairbun officially named Emily now, sort of like how all instances of Megan are Megan even though she's only called that once? I know all the names here are just placeholders of convenience, but even then I've never know what the rules for naming are. [[User:Captain Video|Captain Video]] ([[User talk:Captain Video|talk]]) 06:11, 2 December 2021 (UTC)
: Well, Megan is referred to multiple times in the xkcds as "Megan", while the one time Hairbun was called Emily, it referred to the real{{citation needed}} Emily Dickinson. So, probably not. [[User:Bubblegum|bubblegum]]-[[User_talk:Bubblegum|talk]]|[[Special:Contributions/Bubblegum|contribs]] 02:44, 3 December 2021 (UTC)

Edge pieces on cake are often sought after because they hold more frosting, for cakes which are frosted while out of the pan. [[Special:Contributions/172.70.134.23|172.70.134.23]] 06:37, 2 December 2021 (UTC)
: I have an impression that Cueball is delighted by having only edge pieces, however some cakes edge pieces may be either sought for or avoided, depending on one's tastes. E.g. tarts have more crispy base cake content and less filling at the edges. One person may go for the filling, another for the crispy base. -- [[Special:Contributions/162.158.102.11|162.158.102.11]] 09:50, 2 December 2021 (UTC)

So it seems the events in the comic happened on Apr 1., as the "last month" birthday could be either Feb 28. or 29. -- [[Special:Contributions/162.158.102.11|162.158.102.11]] 09:50, 2 December 2021 (UTC)
:Not necessarily. Remember, Emily can have her birthday ''whenever she wants'', so the date this comic is set as is entirely arbitrary. [[Special:Contributions/172.70.178.51|172.70.178.51]] 12:26, 2 December 2021 (UTC)

Are there any particular existing arctic international flights that could have been the one Emily was born on? -- [[Special:Contributions/256.256.256.256|256.256.256.256]] 15:51, 2 December 2021 (UTC)
:There are a few possibities (at least pre-COVID, and obviously we'd be looking historically in this case anyway) as [https://interestingengineering.com/polar-routes-flights-that-go-over-earths-poles might be shown here]. There's two possible (but neither definite) International Datelines on the comic diagram, in case they help orient which from/to directions might have been diverted further in or out of their own kinks in the flightpath to coincide with 90°N. [[Special:Contributions/172.70.162.77|172.70.162.77]] 16:21, 2 December 2021 (UTC)

Expanded copies of this comic have been appearing on other comics, so large that it fills the whole screen for me. Is anyone else having this problem? [[User:Sarah the Pie(yes, the food)|Sarah the Pie(yes, the food)]] ([[User talk:Sarah the Pie(yes, the food)|talk]]) 22:24, 2 December 2021 (UTC)
:Someone (check the [[Special:RecentChanges|Recent Changes]] page, if you want) has been vandalising a lot of things. Currently I see a picture of an amphibious avian creature on this article's top (if I still need to revert it myself, I will do, but I've seen others have already been reverting other recent vandalism, so I may not need to by the time I've checked again). This very clever individual is obiviously mentally superior to us all(!) the way they can edit wiki pages seemingly at will... Impressive, eh? At some point I'm sure we'll get back to normlal, however boring that may be. [[Special:Contributions/172.70.90.67|172.70.90.67]] 23:33, 2 December 2021 (UTC)

Not to be too pedantic but isn't rotation a FREQUENCY, not a SPEED? [[User:Skulker|Skulker]] ([[User talk:Skulker|talk]]) 03:19, 3 December 2021 (UTC)
:Depends on the context (and scale). The convention is usually speed for rotation (surface(distance/time) when it's relevant, angular(revolutions/time) otherwise) to avoid conflicts with wave frequency (which is independent of speed). Also they can be freely converted, though converting to and from surface speed requires an additional radius term. The exception is, if comparing periodicity, sometimes frequency is used when it has special relevance (Ex: resonance) -- [[Special:Contributions/172.69.68.200|172.69.68.200]] 02:59, 4 December 2021 (UTC)

Tempted to add a link in the Trivia section to the [https://en.wikipedia.org/wiki/SS_Warrimoo Wikipedia] or [https://www.snopes.com/fact-check/ss-warrimoo/ Snopes] pages on the SS Warrimoo, a ship that (reportedly) was on the intersection of the Equator and the International Date Line at the stroke of midnight on January 1, 1900, with a number of interesting implications that follow. There's no way to prove that it actually happened, but it's fun to imagine and is somewhat similar to the premise of the comic. [[User:MeZimm|MeZimm]] ([[User talk:MeZimm|talk]]) 14:33, 3 December 2021 (UTC)
:What convinces me that it's a post-constructed yarn, rather than a legitimate account of a plausible event, is that the 1899-1900 'specialness' is (numerically aside) significant only from a more modern viewpoint. The dominant view at the alleged time of the incident, was the 1-rooted changeover between Centuries (1801 through to the end of 1900, then 1901-2000 to follow), and only changed as the more classical form of education/opinion phased out of common use. It was either later contrived from whole cloth as a tall-tale (if done at the time, it would have been given a 1900/1901 timestamp) or gradually embroidered with all the extra coincidental boundary-crossings (spatial and temporal) well after the actual inspirational seed incident in order to make a better anecdote/shaggy-dog-story.... [[Special:Contributions/172.70.86.12|172.70.86.12]] 15:33, 9 December 2021 (UTC)
:::Okay... but it's fun to imagine... and is somewhat similar to the premise of the comic. And I'd say it's a good deal more plausible than the situation presented in the comic. [[User:MeZimm|MeZimm]] ([[User talk:MeZimm|talk]]) 16:30, 14 December 2021 (UTC)

Many airplanes actually have limitations written into their operating manuals that prohibit flying north of 89 deg. N or south of 89 deg. S, mostly just so that the navigation software doesn't have to deal with the singularity. [[Special:Contributions/172.69.71.187|172.69.71.187]] 23:48, 3 December 2021 (UTC)
:bloody lazy engineers! [[Special:Contributions/108.162.219.107|108.162.219.107]] 12:19, 5 December 2021 (UTC)

Is it not possible that Emily's birth happened to occur at the same moment that the contract specified transfer of ownership? Additionally, is it not possible that the airplane took off from within UTC+13:00 or UTC+14:00 and that the moment of Emily's birth happened to occur in the brief one-or-two hour period in which it was March 1st at that airport, but February 28th in UTC-12:00? UTC-11:00 is inhabited, so it would be possible that ownership of an airplane that took off from within UTC+14:00 was transferred to a company based out of UTC-11:00 during the one-hour period that it was February 28th in UTC-11:00 and March 1st in UTC+14:00 and that, at that exact moment, it was passing over the North Pole. [[User:DL Draco Rex|DL Draco Rex]] ([[User talk:DL Draco Rex|talk]])

Am I alone in thinking that babies don't get born instantaneously? I've never given birth myself but i'd always got the impression that it's a process and any attempt to pick a precise 'instant' is going to be somewhat arbitrary. This means that the plane will very probably have travelled through a variety of time zones any of which could be the 'real' time of birth. [[Special:Contributions/172.70.85.155|172.70.85.155]] 05:29, 4 December 2021 (UTC)
:Time of birth is an arbitrary decision made by the midwives filling out forms in a hospital. The more unlikely point about that is that she'd be able to correlate the precise position of the plane at the exact time listed. [[Special:Contributions/108.162.219.187|108.162.219.187]] 12:37, 5 December 2021 (UTC)

Dickenson looks like a typo. Dickinson? [[Special:Contributions/172.70.162.77|172.70.162.77]] 08:44, 4 December 2021 (UTC)

Isn't an "all edge pieces cake" just a plate of cupcakes lol? [[User:Zman350x|Zman350x]] ([[User talk:Zman350x|talk]]) 06:46, 5 December 2021 (UTC)
:Only if you frosted all sides of it.[[Special:Contributions/172.70.114.3|172.70.114.3]] 12:25, 5 December 2021 (UTC)
:Alton Brown made a similar argument, but after experimenting, I strongly disagree. As with brownies, the cooking pattern is slightly different between having more edges and having a cupcake shape. In an edge piece, the edges and the corners are crisp while the center is gooey. Meanwhile, if cooked in a cupcake tin, while there might be more crispness, there is significantly less gooeyness. [[User:Cwallenpoole|Cwallenpoole]] ([[User talk:Cwallenpoole|talk]]) 14:23, 6 December 2021 (UTC)
:If you cut the sheet into quarters or if the whole was round and cut with radial slices there won't be any center piece(s). And there are more, unusual cuts that could result in all edge pieces...[[Special:Contributions/172.70.34.165|172.70.34.165]] 14:40, 6 December 2021 (UTC)
:My take was that a normal cake was baked, frosted and cut (with both edge and center pieces), and only the edge pieces were delivered to Emily.
::Only a cake baked in a fractal pan would be good enough for her!

Any commentary on the fact that the middle panel shows 25 time zones? [[User:Inca hoots|Inca hoots]] ([[User talk:Inca hoots|talk]]) 16:12, 9 December 2021 (UTC)

this comic has the same number as the carrier pigeon RFC, 2549. maybe related? [[Special:Contributions/172.70.114.251|172.70.114.251]] 19:37, 31 March 2022 (UTC)Bumpf

An edit was made to comment out the "two different decades" aspect, with inline explanation:
this is wrong: the turn of a decade always happens between YYY0 and YYY1, the same as for centuries and millennia
But it is not wrong. Ordinality does not generally apply in this case. Yes, if we describe any period as the "Nth decade/century/millenium", the 'correct' system starts at an appropriate 1-mark (as "Nth year" does) and goes to a 10-/100-/1000-mark which precedes the next "...and 1"-mark. But beyond the first century CE, or so, such an ordinal decadality tails off from practical use. 
A decade would normally be described as "the 1890s", not "the 190th decade", so anything that's "189_" is in the 19thC's century's '90s. Everything "190_" is a new decade (the "oh"s, or whatever variation it would be called), ''mostly'' in the 20thC, under the interpretation applied to the century (the 1-based one) by that editor's standards. "The 1900s" would be non-ordinal description of either the decade (190_ years) or century (19__ years), which perhaps context makes clear. In that respect, however, the former is entirely within the latter. 
I also redid the seasonal thing. Most meteorological "winter months" groupings have the whole of December lumped in with January and February (or summer months, for those south of the equator). Actual equinoxial season changes would switch either on or within a couple of days of 21/Dec (and {{w|Quarter days|any that treat}} "midwinter equinox" as truly ''mid''winter, and likewise with summer, are adrift by about 1.5 months). No other traditional season-markers, perhaps originally either astronomically or meteorologically inspired but with historic drift, seems to be using the modern 31Dec/1Jan point as a boundary. Though historically it has been true that years ticked over at the change of a season, that was often the different interpretation of the year (e.g. the one in which '''Dec'''ember was the '''ten'''th of the twelve months), held over (in Western calendars) only as some of the {{w|fiscal year}) variations that don't align to calendar years. [[Special:Contributions/82.132.237.234|82.132.237.234]] 16:34, 8 October 2025 (UTC)

2549: Edge Cake

2025-10-08T15:41:00Z

82.132.237.234: /* Explanation */

{{comic
| number = 2549
| date = December 1, 2021
| title = Edge Cake
| image = edge_cake.png
| titletext = Every time IERS adds or removes a leap second, they send me a birthday cake out of superstition.
}}

==Explanation==
[[Megan]] — possibly an {{w|IERS}} (International Earth Rotation and Reference Systems) agent — wishes Emily, represented as [[Hairbun]], Happy Birthday. This prompts a confused [[Cueball]] to ask if her birthday was sometime last month. Emily explains that she was born over the North Pole in a plane, meaning that she was born in every timezone at once. Technically though this is false, as there are some timezones (such as {{w|Nepal Standard Time|UTC+5:45}}) that are not represented at the north pole. Except for the one hour before it is midnight at the International Date Line, the date in eastern time zones is one day ahead of western time zones, so Emily would have been born on two days at once.

She also says that it was February 29 (presumably it was also February 28 or March 1 in some time zones). February 29 only happens at most once every four years in the Gregorian calendar, adding to the confusion — people born on February 29 often celebrate their non-leap-year birthdays on arbitrary days (or {{w|The Pirates of Penzance#Synopsis|not at all}}). Normally {{w|Birth aboard aircraft and ships|one could simply use the time zone of the city the airplane took off from}}, but the airline company was changing ownership from one country to another at the time, so this option has apparently been ruled out. This is not terribly logical, however, since contracts transferring ownership usually specify an exact time (commonly one minute before or after midnight in a specific time zone to avoid confusion on which day midnight is in) to come into effect. Regardless of which time zone(s) she was in when she was born this is an absolute time and if she was born before it she would have been born in an aircraft of the first country and if after it in an aircraft of the second country. Alternately, the time zone of the city the aircraft took off from doesn’t change even if the nationality of the plane changes in midair, so that should have still been an option.

The punchline is that rather than try to identify the correct birthday for Emily, the {{w|BIPM}} has decided to let her have birthdays whenever she wants. This doesn't make much sense, however. As noted above even if she was born in every time zone at once it could only have been on one of two days (February 29, plus either February 28 or March 1). Since it is common for people born on February 29 to celebrate on February 28 in non-leap years, it would have been trivial to pick the non-leap day present in some of the time zones (either February 28 or March 1) and declare it Emily's birthday. It is possible that Emily was told, "You can choose when you want your birthday to be", and Emily decided to exploit the lack of specificity to the degree presented in the comic.

In real life researchers in the Arctic at or near the North Pole use {{w|Coordinated Universal Time}} as the [http://www.thoughtco.com/the-north-pole-1435098 local time standard] by convention, to avoid this exact problem. Thus it could have been said that Emily was born on the date that it was at that time in UTC. Furthermore, it is extremely unlikely that she would have been born at the exact instant the plane was over the north pole, indeed, it is unlikely that the plane even traveled over the exact pole, as opposed to a few miles or even feet to either side of it. With modern positioning equipment such as GPS, it should have been possible to determine which time zone the plane was in when she was born. Even in the impossibly unlikely event that she was directly above the pole at the instant of her birth, at jetliner speeds the plane was traveling about ten miles per minute, so a reasonable delay of even seconds in declaring "time of birth" would have placed the plane and her clearly in one time zone.

Both the comic title and Cueball's final line are puns on "{{w|edge case}}", an engineering term referring to situations or conditions that are unusual in a way likely to cause problems unless specifically accounted for. Edge pieces are generally only important with sheet goods (brownies, sheet cakes, etc), which are typically cut into pieces creating a difference between pieces originating on the edge and pieces originating from the center. Since the top and sides of a cake are often frosted, an edge piece has two faces covered in frosting and a corner piece has three, while a center piece only has one. Depending upon your relative preferences between the surface (often icing over marzipan) and core body of the cake (which can be fruitcake, or some variety of spongecake, etc., but not actually obvious which until the cake is cut), it being an edge-faced slice can be considered a bonus. Cueball certainly seems to appreciate this.

The title text states that the {{w|IERS}} sends Emily a cake every time they add or remove a leap second, out of superstition (perhaps Megan is delivering that cake). The International Earth Rotation and Reference Systems Service is in charge of global time standards. It occasionally adds one leap-second to {{w|Coordinated Universal Time}} to adjust for changes in the rotation speed of the Earth.

The comic might also be a modern version of the ''{{w|SS Warrimoo}}'', a passenger liner that reportedly crossed the international date line at the equator on midnight December 31, 1899. This would have placed her bow in the Southern Hemisphere on January 1, 1900, her stern in the Northern Hemisphere on December 31, 1899. She would therefore have been simultaneously in two different hemispheres, on two different days, in two different months, in two different years and in two different decades. By {{w|Century#Start and end of centuries|some definitions}}, possibly also in two different centuries, though this precludes being in two different ''seasons'', by all {{w|Winter#Meteorological reckoning|common}} {{w|Winter#Astronomical and other calendar-based reckoning|variations}} of their definition.

==Transcript==
:[Megan is walking towards Cueball and Emily (who resembles Hairbun), holding a cake.]
:Megan: Happy birthday, Emily!
:Cueball: Wait, wasn't that last month? When's your birthday, anyway?
:Emily: It's complicated.

:[A diagram of a flight path over the North Pole, with meridian lines radiating out from the center. Emily's dialogue appears above the diagram, but she herself does not appear in this panel.]
:Emily: My mom went into labor on an arctic international flight that diverted directly over the North Pole.
:Emily: I was born in every time zone at once.

:[With Megan standing behind her, Emily holds out a plate of cake to Cueball.]
:Emily: It was also February 29th, and the airline was just changing ownership between countries.
:Emily: The International Bureau of Weights and Measures finally issued a declaration that it's my birthday whenever I want.
:Emily: Cake?
:Cueball: Nice, it's all edge pieces.

==Trivia==
*Hairbun was last named "Emily" in [[788: The Carriage]].
**More specifically, that version of Hairbun represented {{w|Emily Dickinson}}, a real, historical person who had no such issues regarding her birthday.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Hairbun]]
[[Category:Aviation]]
[[Category:Time]]
[[Category:Engineering]]
[[Category:Science]]

2676: Historical Dates

2025-10-08T15:11:02Z

82.132.237.234: Most of that added smartquotes (unintentionally, due just to the method of editing?). The date-format changes might have been valid-to-neutral, but I have no problem with their revert either.

{{comic
| number = 2676
| date = September 23, 2022
| title = Historical Dates
| image = historical_dates_2x.png
| imagesize = 305x438px
| noexpand = true
| titletext = Evidence suggests the 1899 transactions occurred as part of a global event centered around a deity associated with the lotus flower.
}}

==Explanation==

Many files and database entries contain a date. When it is not set, it often defaults to the first day in the system. The two dates listed below are mentioned as "significant" in the comic.

===Dec 30th, 1899===
Dec 30th, 1899 comes from a [https://www.joelonsoftware.com/2006/06/16/my-first-billg-review/ spreadsheet date compatibility issue] between Excel and Lotus 1-2-3 (referenced in the title text.) Spreadsheets store dates as sequential numbers so that they can be used in calculations. In Excel, by default, January 1, 1900 is number 1 [https://support.microsoft.com/en-us/office/datevalue-function-df8b07d4-7761-4a93-bc33-b7471bbff252]. Based on that, Excel's integer date representation would be the number of days that have passed since December 31, 1899. However, because of a bug intentionally carried over from Lotus 1-2-3 where it counts February 29, 1900 as a day even though it actually was not [https://learn.microsoft.com/en-us/office/troubleshoot/excel/wrongly-assumes-1900-is-leap-year], for any day since then, Excel's integer date representation is actually the number of days that have passed since December 30, 1899. Most other spreadsheet applications copied the behavior of Excel to maintain compatibility with it. This leads to the value of 0 in some applications (notably Open- and LibreOffice Calc and Google Spreadsheets) being interpreted as Dec 30th, 1899. Similarly, Microsoft Visual Basic and Visual Basic for Applications (VBA) interpret 0.0 as Dec 30th, 1899.

The historian in the comic presents some research wrongly based only on the number of entries created on those dates. This confusion on the part of the future historian only grows in the title text, where they make the claim that Lotus 1-2-3 is, in fact, religious imagery related to some sort of deity, potentially a lotus god, around whom the '1899 event' took place. This may be poking fun at the trope that anthropologists attribute any behavior they can't explain to religious ritual.{{Actual citation needed}} This historian's confusion may have been at least partially due to China's {{w|White Lotus|White Lotus Religion}}.

===Jan 1st, 1970===
Many operating systems and software store dates as {{w|Unix time|Unix timestamps}}, which are defined as the number of seconds since Jan 1st, 1970, 0:00 UTC. When data entry neglects to provide a value, the system may be programmed to treat it as 0; consequently, an unprovided timestamp value is interpreted as Jan 1st, 1970 thereby creating the illusion of an "activity spike" on that date.

==Transcript==
:[Blondie is lecturing, pointing at a futuristic holographic display emanating upwards from a unit on the floor. It shows a presentation that features a timeline with two visible dates, 1899 and 1970. At the top of the hologram are two lines of text, above "1899" are three lines of text, above "1970" is one line of text, below "1899" are two lines of text, and below "1970" is one line of text; all of these lines of text are illegible.]
:Blondie: Historical records show millions of business transactions occurred on Dec 30th, 1899.
:Blondie: This economic activity sparked the digital age, culminating in a "data festival" on Jan 1st, 1970, when many early digital files were created.

:[Caption under the panel:]
:It's going to be weird when historians forget why some dates show up a lot.

{{comic discussion}}

[[Category:Calendar]]
[[Category:Time]]
[[Category:Programming]]

2867: DateTime

2025-10-08T15:07:53Z

82.132.237.234: /* Explanation */ Rewinding all the improperly added smartquotes (MOS:QUOTEMARKS). Some other tidying up, mainly involving spaces.

{{comic
| number = 2867
| date = December 13, 2023
| title = DateTime
| image = datetime_2x.png
| imagesize = 679x478px
| noexpand = true
| titletext = It's not just time zones and leap seconds. SI seconds on Earth are slower because of relativity, so there are time standards for space stuff (TCB, TGC) that use faster SI seconds than UTC/Unix time. T2 - T1 = [God doesn't know and the Devil isn't telling.]
}}

==Explanation==

[[Ponytail]] asks [[Cueball]] how to calculate the time elapsed between two instants. A Cueball not intimately familiar with the complexities of the way humans measure time naively assumes that this is given by the difference of the timestamps. A Cueball who is familiar panics and states that it is impossible to know, and further that it is forbidden to even ask the question.

Randall's use of the term "DateTime systems" covers [https://metacpan.org/pod/DateTime any] [https://docs.python.org/3/library/datetime.html number] [https://learn.microsoft.com/en-us/dotnet/api/system.datetime?view=net-8.0 of] [https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date situations], and the complexities are hardly confined to any particular programming language, or indeed computers as a whole. Some of these complexities include time zones (and changes to time zones), the international date line, daylight saving time and differing observation (or non-observation) thereof in different areas (and changes to the observation of daylight saving time over time), leap days and leap seconds, etc. Another complexity is found in relativistic effects, in which the flow of time varies depending on how deep in a gravity well one is; {{w|Barycentric Coordinate Time}} and {{w|Geocentric Coordinate Time}} (in French, TCB and TCG respectively — the reference to TGC in the title text appears to be a typo) are time systems used for space missions and orbit calculations that handle this and shortly after this comic was published it was announced that [https://www.space.com/white-house-nasa-time-zone-moon Coordinated Lunar Time (LTC)] would be established. A partial list of such minutiae may be found at [https://gist.github.com/timvisee/fcda9bbdff88d45cc9061606b4b923ca Falsehoods Programmers Believe About Time]. The title text of the comic also references some of them. Depending on when T1 and T2 are, changes in calendar system may also be a relevant consideration — perhaps most famously, the change from the Julian calendar to the Gregorian calendar, two calendar systems which are nearly identical but nearly two weeks apart, and which different countries changed at different times.

The statement that "it is impossible to know" is because Ponytail did not provide enough information in the question: She needed to specify the location and time zone of both observations, and possibly the exact values of T1 and T2 to the nanosecond. Considering the restrictions imposed by relativity on two observers agreeing on the timing of events, it may be literally impossible to determine a value of T2 − T1 that is absolutely "correct" to arbitrary levels of precision.

The addition of "and a sin to ask" is hyperbolic. It implies that asking such questions is akin to attempting to acquire forbidden knowledge of the nature of God or the Universe, for example, through practices such as {{w|Numerology}}, which some may consider heretical. It is an expression of the fact that determining the answer accurately can be complicated, and programming systems that attempt to do this can be frustrating.

"T2 − T1 = [God doesn't know and the Devil isn't telling.]": This is a colloquial expression that riffs on the more common "God only knows", as well as "Hell knows and Heaven suspects", to suggest that the thing in question is even more unknowable than the usual type of unknowable thing, to the point where it may be an evil invention of the Devil designed to cause complexity and frustration for the people having to deal with it.

Programmers coming here in despair should refer to their language standards and [https://www.w3.org/International/wiki/WorkingWithTimeZones#Guidelines_Summary|the W3's reasonably complete guidelines for those of us planetside]. Space programmers coming here in despair should note that on long enough timescales, it doesn't matter what time it is ''anywhere''.{{Citation needed}}

==Transcript==
:[Ponytail is talking to Cueball.]
:Ponytail: Event #1 happened at time T1.
:Cueball: Okay.

:Ponytail: Then event #2 happened at time T2.
:Cueball: Mhmm.

:Ponytail: How would you calculate how much time elapsed between T1 and T2?

:[The comic splits into two paths, each with a caption at the top.]

:[Path 1, upper right panel]
:Caption: Normal person:
:Cueball: T2 minus T1.

:[Path 2, lower right panel]
:Caption: Anyone who's worked on datetime systems:
:[Cueball has his arms raised.]
:Cueball: '''''It is impossible to know and a sin to ask!'''''

{{comic discussion}}

[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Cueball]]
[[Category:Time]]