Line #55 Main/YearZero


1	Year Zero is an event used to reckon time within a particular continuity or universe, especially by fandom.
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3	While seemingly as arbitrary as ''any'' hypothetical calendar is, it avoids being too specific while still setting a hard date on important things. This is useful if a writer wants to avoid accidentally invoking PeriodPiece baggage by using certain dates, but also an easy way to set events by the narrative rather than the implication that time is passing in a strictly consistent way. In some works Year Zero is generally the "hardest", and sometimes only, date relevant to actual characters. Most of the story takes place in the conveniently nebulous period after it. Because lying between two hard dates could be restrictive given enough time, events are reckoned as before or after Year Zero instead.
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5	Occasionally writers slip and throw in an actual date, especially in [[EarlyInstallmentWeirdness early versions or installments]] of works before the writers became concerned with looking dated. Fans tend to jump on these while working out timelines.
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7	For obvious reasons, Year Zero is often invoked for authors who use [[ComicBookTime sliding timelines]]. For example, the formation of the ComicBook/FantasticFour was occasionally used as the Year Zero of Creator/MarvelComics continuity, with 'present-day' stories occurring about 10 years after this. [[ContinuitySnarl This does not always work perfectly.]]
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9	See also AlternativeCalendar, for ways of reckoning time in-universe. Events that prompt these alternatives have HitSoHardTheCalendarFeltIt.
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11	Compare EpisodeZeroTheBeginning.
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13	----
14	!!Examples:
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16
17	[[folder:Anime]]
18	* ''Franchise/{{Gundam}}'' has a different Year Zero for each of its {{Alternate Universe}}s, though they were invented by the creators rather than the fans. Interestingly, each series takes place decades after its timeline's Year Zero, and only rarely is the Year Zero explicitly tied to a specific event.
19	** U.C. 0001, the first year in the original ''Anime/MobileSuitGundam'''s Universal Century, is the year in which migration to space begins, and as revealed in ''Anime/MobileSuitGundamUnicorn'' (the first UC series to make reference to that year) is also tied to the actions of a young Syam Vist.
20	** In ''[[Anime/MobileSuitGundamSeed Gundam SEED]]'', the Year Zero appears to be a Year 1: The Cosmic Era calendar is adopted in roughly 9 CE, and is retroactively dated to begin when [[HitSoHardTheCalendarFeltIt nuclear weapons were used in Kashmir]] nearly a decade before. Three new superpowers and a number of new smaller powers also emerge from the radically changed national order. Following other Gundam timelines, the UN also announces a new Space Exploration and Colonization program. Much like other timelines, it's not mentioned when the exact date AD became CE, other than that it was sometime in the mid- or late-twenty first century.
21	** Fans tend to attempt to create the regular version of this with at least the Universal Century timeline, since there are a handful of specific dates given that are tied to a day of the week. This can be used to narrow down 2047 as the earliest possible year for the switch to the new calendar (2045 is the last AD date mentioned in any official timelines, but based on [[Anime/MobileSuitGundam0080WarInThePocket January 14th 0080 falling on a Monday]] and [[Anime/MobileSuitGundamZZ 0088 being a leap year]] the changeover couldn't have happened then, assuming they didn't skip any dates or change the way leap years are distributed when the calendar was overhauled. It's also worth noting that WordOfGod has since declared all the official timelines that mention the AD era non-canon).
22	** The After Colony calendar in ''[[Anime/MobileSuitGundamWing Gundam Wing]]'' on the other hand, is implied begin from the launch of Skylab in the 1970s. Though it's never mentioned exactly when AC replaced AD.
23	*** The novelization of the TV series drops two important bits of information in a single sentence: The circus where Trowa Barton hides out was founded in 1667 and has been around for almost 600 years. This puts AC 195 (the year the TV series takes place) in the neighborhood of 2260 AD, which would place Year Zero some time around the [=2070s=].
24	* ''Franchise/LyricalNanoha'' measures time based on the new Mid-Childa calendar, which according to the Fate's AsYouKnow talk in episode 14 of ''Anime/MagicalGirlLyricalNanohaStrikers'', began during the period when physical-based weapons were banned and {{Magitek}} became the standard. This was the time when the TSAB had fully established themselves, building their main branch in Dimensional Space and their land-based HQ in Mid-Childa.
25	* When Kagome travels to the past in ''Manga/InuYasha'', she plops down into Japan's UsefulNotes/SengokuJidai, a century of continuous civil war and bloodshed. Because no exact dates are mentioned it would be anyone's guess as to what year it is when she goes back in time. The main clue the fandom has used to try to put a date to the era comes from one of the very first episodes, where a young samurai mentions UsefulNotes/OdaNobunaga, but considers him to be an unimportant idiot.[[note]]Nobunaga eventually brutally conquered much of Japan and his successors finished the unification and established the government that ran the country for the next 250 years[[/note]] Since there is a rather short window of time where Nobunaga was known, but ''not'' as a terrifying, ruthless, slaughter-happy badass, fandom uses this to get a rough idea of when the story is supposed to be taking place, with the fandom generally agreeing on a period between about 1550 to 1560.
26	* ''Manga/OnePiece'':
27	** The Year Zero event is generally portrayed as the founding of the World Government, which occurred approximately 800 years ago. This event is the foundation of the ''One Piece'' world as it is now and the end of the "Void Century", a period which has very few surviving historical records and is illegal to study.
28	** Another Year Zero used unofficially in-story is the death of Gold Roger, twenty-four years prior, which started the "Great Pirate Era." Many characters refer to the "current era" and how it started with Roger's death. Some also remark that [[spoiler:Whitebeard]]'s death is yet another Year Zero, creating a new era.
29	** A more subtle example would be in the New Fishman saga. [[spoiler: The oldest of the Fishman princes desires to return it all to 'zero.' This refers to wanting to undo and do away with the bigotry the fishman/merfolk have with humans and vice versa. It's achieved when Luffy stops Hody, saves the island and is given blood by Jimbei, symbolic as it was forbidden to give humans blood due to a past event involving Fisher Tiger. The prince notes to his deceased mother that they achieved, expressing the desire for a better future for the races,]]
30	** Curiously, the only year numbering actually seen in the series (Age of the Sea) matches none of these, beginning approximately 1500 years before the series. The event that it is based on is unknown.
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33	[[folder:Comic Books]]
34	* After the CrisisCrossover ''ComicBook/ZeroHourCrisisInTime'', Creator/DCComics put out a timeline showing where different events had happened in current continuity relative to "X years ago", thus sidestepping the question of ComicBookTime.
35	* ''ComicBook/FantasticFour'' is the starting point of Marvel's sliding timescale, which roughly works like this; the time in Marvel is always "now", and everything in continuity is supposed to have happened within around a 10 to 14-year timespan. It is called a sliding timescale because the fact that the end point is always the present drags older stories forward in time; this can pose problems for heroes with ties to a specific era. Sometimes details can change: Iron Man originally had his original story in the Vietnam War, though this has now been changed to the Middle East (at least in the Franchise/MarvelCinematicUniverse), but characters tied to a specific era don't always work as well - while they just need to lengthen the amount of time Captain America (a WWII veteran) spent frozen, Magneto (a Holocaust survivor) and Professor X (a Korean War vet) are forced to be older and older, eventually forcing the creation of storylines in which they are de-aged or moved into younger clone bodies or what have you.
36	** In the 2019 miniseries ''Comicbook/HistoryOfTheMarvelUniverse'' this was (seemingly) settled once and for all by the insertion of an Asian conflict set in the fictional country of Siancong. Called a "decades-long war," it can slide along the timeline and provides an anchor for many characters whose histories were previously rooted in real-world conflicts, including the Punisher (originally a Vietnam vet), the aforementioned Iron Man, and Reed Richards and Ben Grimm, who in 1961 were written as World War II vets, but which was later dropped as the war fell further and further into the past.
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39	[[folder:Film]]
40	* In ''Film/TwoThousandTwelve'', after TheEndOfTheWorldAsWeKnowIt, the remains of mankind restart the calendar.
41	* ''Germania anno zero'' (English trans. ''Germany, Year Zero'') was a 1948 Italian film set in post-WWII Berlin. Protagonist Edmund Kohler [[ComingOfAgeStory (age twelve)]] struggles to survive in a chaotic world: little rebuilding has been accomplished, food and necessary supplies are rationed & shortages are common. Edmund escapes the tense, claustrophobic apartment in which he resides along with remnants of five families to the streets, hoping to scavenge useful items or information. [[FromBadToWorse Things get worse]].
42	* ''Film/TheKillingFields'': After the Khmer Rouge take over Cambodia, they attempt to erase any and all memory of life before they came to power, which among other things includes a new calendar that starts at year zero. TruthInTelevision, as the Khmer Rouge [[https://en.wikipedia.org/wiki/Year_Zero_(political_notion) actually did this]]; it was inspired by the short-lived [[https://en.wikipedia.org/wiki/French_Republican_calendar French Republican Calendar]], which reset everything to year one.
43	* ''Film/PanicInYearZero'' is about the aftermath of a nuclear war; the United Nations decides to reset the calendar as "Year Zero".
44	* Time in ''Franchise/StarWars'' is generally measured in relationship to ''Film/ANewHope''. This was eventually given a [[FandomNod nod]] with the introduction of an in-universe calendar established by the New Republic based on that same date, specifically, the [[http://starwars.wikia.com/wiki/Battle_of_Yavin Battle of Yavin]]. The ''Star Wars'' BBY/ABY (Before/After Battle of Yavin) calendar differs from most real-life examples in that the zero year is expressed as both 0 BBY and 0 ABY. The transition between BBY and ABY happened at the exact moment that the Death Star was destroyed.
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47	[[folder:Jokes]]
48	* A 12th century farmer's son named John is helping his father unload cabbages at the market, when suddenly he lets loose a fart so massive it causes heads to turn all the way down the end of the market. The boy drops his cabbage and runs until he's out of the market, then out of town, and keeps running. Years pass, during which he joins a mercenary band, gets kidnapped by pirates, gets shipwrecked, wins fights, makes fortunes, loses them, goes around the Mediterranean twice, until one day he realizes that his wanderings have brought him back to his hometown. As it's been decades since he last saw it, he goes in, and notices a magnificent cathedral. Seeing a small child nearby, he asks when it was built. The child answers:
49	-->It started three years, two months and twelve days, then finished twenty-three years, five months and three days after The Day John Farted.
50	[[/folder]]
51
52	[[folder:Literature]]
53	* In the early days of ''Literature/HarryPotter'', fans had to measure time from Harry's first year at Hogwarts. Thankfully for timeline-makers, ''[[Literature/HarryPotterAndTheChamberOfSecrets Chamber of Secrets]]'' [[FandomNod threw in a line]] (specifically, Nick's Deathday date) that placed the first book in the 1991-92 school year. ''[[Literature/HarryPotterAndTheDeathlyHallows Deathly Hallows]]'' established the same time frame through the dates on James and Lily Potter's graves. Despite several uses of post-1998 technology and London landmarks, due to the [[Literature/HarryPotterAndTheOrderOfThePhoenix last]] three [[Literature/HarryPotterAndTheHalfBloodPrince books]] being written across the 2000s, [[Film/HarryPotter the films]] (filmed from 2000-2010) also have gravestones dating the films' "present day" to this period.
54	* Though there were always some details here and there that showed in what year the Literature/SherlockHolmes stories were set, there was always the question of how old Holmes was--whether he was in his 20s, 30s or 40s during ''Literature/AStudyInScarlet'' (his first appearance). It wasn't until ''His Last Bow'' (which was supposed to be the GrandFinale) that Conan Doyle decided to give Holmes an age of 60 during 1914, meaning that he was born in 1854 and was 27 years old during ''A Study in Scarlet'' (set in 1881).
55	* J.R.R. Tolkien's timeline in both ''Literature/TheHobbit'' and ''Literature/TheLordOfTheRings'' was meticulously kept. Frequent dates were given on the in-universe calendar (in the case of The Lord of the Rings both in Shire Reckoning and the larger calendar of Middle-earth). Additionally, each culture kept time based on their own internal reckoning, with years based on significant events: The Hobbits followed Shire Reckoning, with Year Zero on the founding of the Shire, while Gondor and Rohan had their own calendars as well. Middle-earth on the whole broke timekeeping down into different Ages whose first year was decided by specific events. Tolkien paid so much attention to his calendar system that he even rewrote the ''entire chapter'' of Faramir and Frodo overlooking the waterfall at Henneth Annûn because he realized that the phases of the moon he used didn't match his previously established timeline!
56	** The timeline for the Silmarillion, however, is somewhat more confused and murky, possibly owing to his death before completing it. Exactly how the Valian Years, the Years of the Trees and the Years of the Sun in the First Age connect is left unclear.
57	* In ''Literature/ASongOfIceAndFire'', Year Zero in the Seven Kingdoms is dated from the crowning of King Aegon I the Conqueror, founder of the Targaryen dynasty. The main series starts 298 years later.
58	* At the end of ''Literature/{{Anathem}}'', the main character notes that the current day is "Day Zero, Year Zero". Given that [[spoiler:their discovery of, and contact with, other universes has changed society a lot]], this is to be expected.
59	* In the ''Literature/HonorHarrington'' universe as a whole, Year Zero is the Diaspora, when humanity left earth for the stars. All years are usually referred to as Standard Years Ante or Pre-Diaspora. Planets also have their own local calendars, using the initial landing of colonists as their respective Years Zero.
60	* Also from David Weber is ''Literature/{{Safehold}}''. As far as Safeholdians know, Year Zero is the day of Creation itself. Though following the Archangel Shan-wei's rebellion, a new calendar was established using the end of that war as the Year Zero. This becomes a fairly significant plot point in the later books, [[spoiler: since they learn from Paityr that the Archangels are prophesied to return after a thousand years. If that's a thousand years from Creation, the inner circle only has about twenty more years before their return, whereas if that's counting from Shan-Wei's murder they have close to a century.]]
61	* In Frank Herbert's ''Franchise/{{Dune}}'', the imperial calendar starts at the creation of the Spacing Guild, which holds a monopoly over interstellar transportation. The coronation of the first Corrino Emperor and discovery of the spice happened around the same time: the end of the Butlerian Jihad, the Great Revolt in which humanity destroyed the "Thinking Machines" that had enslaved most of them. The year at the beginning of the first novel is "10,191 AG". ''However'', the Appendix also states that "one hundred and ten centuries" (11,000 years) passed between discovery of space travel (in the 20th century) and the Butlerian Jihad. Thus the ''actual'' setting of the first novel is roughly ''twenty'' thousand years in the future, double the ten thousand it appears at a casual glance. The 1984 David Lynch movie adaptation mistakenly gives the date as "the year 10,191 ''AD''".
62	* In Robert Reid's ''Literature/YearZero'', citizens of the universe revere artistic endeavors, none more so than music. Turns out that humans make better music than any civilization in the history of the universe. The discovery of Earth's music (sans North Korea) was so monumental that they reset the universal calendar based on the date of discovery of the theme song to ''Series/WelcomeBackKotter''.
63	* In Alex Garland's ''Literature/TheBeach'', members of the beach community commemorate their Year Zero, the founding of the community, with the annual Tet Festival.
64	* In ''Literature/TheLeftHandOfDarkness'', the Karhide calendar counts ''every'' year is Year One and other dates are counted forward or backward from it. Historical discussions usually refer to kings' regnal dates and other great events for consistency. An alternate calendar used by the Yomeshta religion date from their prophet's revelation.
65	* In ''Literature/PerryRhodan'' the "Cosmic Hanse" cycle begins with Perry declaring a new calendar. Even his close friends are a bit shocked.
66	* Year Zero in ''Literature/BraveNewWorld'' is 1908, when Henry Ford is credited as having invented the assembly line, the pivotal event in the far-future dystopian society that views him as a messianic figure. The "present date" is only given according to the Fordian calendar, A.F. ("After Ford") 632.
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69	[[folder:Live-Action TV]]
70	* ''Series/{{Andromeda}}'' measures years in Commonwealth Years, which starts with the beginning of the Vedran Empire, making time in the series very non-specific. However, [[AllThereInTheManual extended material]] gives the Commonwealth date for when Creator/FriedrichNietzsche published ''Literature/ThusSpakeZarathustra'', a definite date in our time system, so assuming they use the same years as we do (years based on the cycle of Tarn Vedra rather than Earth, though the difference can't be too much), it creates a good guess of the timeline of the series.
71	* The [[http://en.battlestarwiki.org/wiki/Timeline_(RDM) Battlestar Wiki Timeline]] measures time from the Cylon holocaust depicted in the ''Series/{{Battlestar Galactica\|2003}}'' miniseries. In-universe calendars are [[https://en.battlestarwiki.org/Colonial_calendar largely inconsistent with each other]], though ''Series/Caprica'' established a year numbering based on the human exodus from Kobol.
72	* The current year is never mentioned in any season of ''Series/TwentyFour'', but the amount of time between days (16 months between Day 1 and 2, three years between Day 2 and 3, etc) is always established and can be used to determine how many years it has been since Day 1. In addition, fans have used various clues to formulate the following timeline:
73	** Day 1: Tuesday, March 2nd, 2004
74	** Day 2: A Saturday in September 2005
75	** Day 3: September 2008
76	** Day 4: March 2010
77	** Day 5: September 2011
78	** Day 6: May 2013
79	** Day 7: February 2017
80	** However the real world events that surround the first season would make this timeline slightly incorrect. The first season is meant to take place around one to two years after Jack's mission in Belgrade. The mission took place when Slobodan Milosevic was still in power which would place the mission in either 1999 or 2000.
81	* The season 2 finale of ''Series/{{Lost}}'' established that Oceanic 815 crashed and started the whole thing on September 22, 2004, the same day that ''The Pilot, Part 1'' episode was first aired. Since then, fans were able to give all events of Seasons 1-4's present day an exact date based on the clues within the series. However, a TimeSkip appeared in season 3 and events from flashforwards in that finale and season 4, and any of seasons 5-6 can only be put down to the year they happen in, with no precise dating except in relation to each other (with the exception of one season 4 flashforward, and time skips in season 5 that overlap with events from the early seasons).
82	* On ''Series/TwinPeaks'', Agent Dale Cooper's first recorded message is dated 24 February, with the year established as 1989 by Ronette Pulaski's hospital chart. WordOfGod is that each episode represents one calendar day with the exception of an intertitle establishing a three-day time skip. This puts the events of the season 2 finale on 29 March.
83	* The stardate system in use on ''Franchise/StarTrek'' implies a year zero (the presumed "Stardate 0000.0") without ever specifying what it ''is''. Averted by later iterations, which convert the Gregorian year into stardates.
84	* ''Series/KamenRiderBuild'' takes place in an AlternateUniverse relative to the prime universe that most of the rest of the ''Franchise/KamenRider'' franchise takes place in, with the big difference being the sudden appearance of the Skywall physically dividing Japan into three countries. The year that the Skywall Disaster happened is 2007, but the three countries have a new calendar that identifies years in relation to this event as '''A'''fter '''S'''ky '''W'''all, with the first year being ASW 001 and the present day events of the series proper starting ten years later in ASW 011 (2017).
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87	[[folder:Music]]
88	* The album ''Music/YearZero'' by Music/NineInchNails is a ConceptAlbum and associated ARG in which 2022 (15 years after the album's release) has been declared "Year Zero" by a corrupt, far-right U.S. government.
89	* {{Invoked\|Trope}} by the [[Music/GhostBand Ghost]] song "Year Zero", which uses the term to reference the time of Satan's conquering of the world.
90	-->Hell Satan, archangelo\
91	Hell Satan, welcome year zero
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94	[[folder:Tabletop Games]]
95	* The title of ''[[TabletopGame/MutantYearZero Mutant: Year Zero]]'' is meant to represent the earliest date in the setting's history, seeing as how it is considered a soft prequel of ''TabletopGame/{{Mutant UA}}''.
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98	[[folder:Video Games]]
99	* ''Franchise/FinalFantasy'':
100	** ''VideoGame/FinalFantasyVII'' has the Shinra Company setting the year zero of its new era at the end of the Wutai War, six years before the start of the game. While not very important in the original game, games set in the prequel portion of the Compilation often make note of the date.
101	** ''VideoGame/FinalFantasyXIII2'' dates things from [[spoiler:the fall of Cocoon]] at the end of ''VideoGame/FinalFantasyXIII''.
102	* ''Franchise/FireEmblem''
103	** ''VideoGame/FireEmblemPathOfRadiance'' and its sequel, ''VideoGame/FireEmblemRadiantDawn'' did this a little differently. There is a year 0, but there are years ''before'' that are listed as negative. [[http://serenesforest.net/general/timeline10.html Year -155 is the earliest.]]
104	** ''VideoGame/FireEmblemThreeHouses'' uses the foundation of the Adrestian Empire as the starting point for its calendar. The official history of Fódlan goes back slightly further than that, with the earliest recorded date being the first sighting of Saint Seiros 41 years before the Empire was formed.
105	* ''Franchise/TheElderScrolls'' universe has several Year Zeros, at the [[HitSoHardTheCalendarFeltIt beginning of every new 'Era']]. It's common practice to put the Era before the year when announcing a date, for example "Third Era, Year 433", which is typically written as "3E 433". The first four games take place in the 5th century of the 3rd Era (roughly - ''[[VideoGame/TheElderScrollsArena Arena]]'' covers the last year of the 4th century), and ''[[VideoGame/TheElderScrollsVSkyrim Skyrim]]'' takes place in the third century of the 4th Era.
106	* Invoked, but not used, in ''VideoGame/GrandTheftAutoSanAndreas''. After grabbing the Green Goo from an armored train for The Truth, he claims "they will call this Year Zero". Sadly, nothing comes of it.
107	* An extremely common {{Fanon}} for ''VideoGame/TalesOfPhantasia'' and ''VideoGame/TalesOfSymphonia'' is that ''Symphonia's'' ending is Year Zero for the calendar used in ''Phantasia''.
108	* The ''Franchise/AceAttorney'' series frequently uses months and days for dates, but it usually refers to years only by reference (two years after a case, 5 years earlier, etc). However, a year is given for one particular event: the DL-6 incident happened in 2001 (December 28, to be exact). From this one fixed point, one can deduce the exact date of pretty much every case and event in the entire franchise.
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111	[[folder:Webcomics]]
112	* The calendar in the Spanish webcomic ''Webcomic/CincoElementos'' is based on a date called "Day Zero", when there was an all-out war that made the whole country collapse (curiously referred to by no other name than the "Day Zero war"). However, no date has been given so far in the comic, we only know the base of the calendar. (In fact, the author played with this in a chapter, trying to get fans off track in the timeline before [[spoiler:revealing that Rubéola wasn't Matarratas's real sister, when Matarratas's father had been stated to be 3 in the Day Zero.]]) Current fan speculation has the first chapter at the year [[spoiler:32]].
113	* Webcomic/StandStillStaySilent counts from "Year 0, Day 0", when the virus that kills off most of humanity first appears. The main storyline takes place starting in Year 90.
114	[[/folder]]
115
116	[[folder:Web Original]]
117	* While ''Website/{{Neopets}}'' has its own in-universe calendar, it is tied to meta causes. The Neopian Year 0 is our 1998, when the initial concept for the site was being created before its launch in November 1999 (Year 1). 1997 is referred to as "Year 1 BN", and so on.
118	[[/folder]]
119
120	[[folder:Western Animation]]
121	* The ''Franchise/AvatarTheLastAirbender'' [[http://avatar.wikia.com/wiki/History_of_the_World_of_Avatar#Dates wiki]] measures time as Before Air Nomad Genocide (BG) and After Air Nomad Genocide (AG). This event is one of the few things that we are given exact dates for, as Aang is explicitly mentioned as having been frozen in the iceberg for 100 years.
122	[[/folder]]
123
124	[[folder:Real Life]]
125	* Happens with particularly radical revolutionary governments, both on the right and left of the political spectrum, whereby a new calendar is instituted to replace the old, signifying a total break with the past and its irrelevance compared to the glory of the new revolutionary movement, often starting with a "Year Zero" or "Year One." The UrExample of this is from the French Revolution, when the Jacobins threw out the old Gregorian "religious" calendar and replaced it with a new "Revolutionary Calendar" starting from Year I; it was only in use for twelve years before the country reverted to the Gregorian calendar. Other examples include Fascist Italy, Communist Cambodia, Communist North Korea, and the Republic of China.
126	* This was averted by the Gregorian calendar system used throughout the world. There is no year zero, and it is one of the calendar's base assumptions. Things that happened before the birth of Christ (the starting point of the calendar) are calculated in negative years Before Christ, counting down not to Year Zero, but Anno Domini 1: that is, there is a direct skip from 1 BC straight to AD 1! (Due to errors in calculations, the actual birth of Christ may lie anywhere from 6 BC to AD 6.)[[note]]The calendar's creator was limited by the fact that his society's mathematicians had no concept of zero yet.[[/note]] The lack of a year zero on the Gregorian dating system has led to many placing the start and end points of each century wrong, particularly in recent decades. For instance, when supercentenarian Emma Martina Luigia Morano died in 2017, it was common to hear sources misreport her as having been the final living person born in the 19th century, when in reality, she was just the last person born in the 1800s. The ''actual'' last living child of the 19th century was Nabi Tajima, born in August of 1900. One notable gag on ''Series/{{Seinfeld}}'' makes light of this common mix-up, in which Newman accidentally books his New Year's Eve party a year later than intended thanks to him asking to reserve it for the New Millennium.
127	** Played straight on both the astronomical calendar and the ISO 8601 specification. Both include a year zero, as the lack of this screws up the math on BC years. Thus, 1 BC is 0, 2 BC is -1 and so on.
128	* The time when Nazi Germany was defeated by the Allies and reconstruction efforts began was known as "Die Stunde Null" or "Das Jahr Null" (Zero Hour / Year Zero) to German citizens. It combined a feeling of defeatism, utter shock, delusion, and hope for the future.
129	* Ever since the UsefulNotes/MeijiRestoration, Japan has used a Regnal Calendar of the regnal names of the reigning Emperor of the time. The current era, for example: ''Reiwa'' began in 2019 when Naruhito ascended the Chrysanthemum throne, which makes 2019 Reiwa 1. His father Akihito's reign was known as ''Heisei'', which began in 1989.
130	* In geology and archaeology (and related scientific fields), past events are referred to in terms of years "Before Present". So that there will only be a single timeline across all scientific papers, a Year Zero for "Present" was chosen as 1950 AD. Aside from being a conveniently recent date (this standard was chosen in 1954), it also a useful dividing line because post-1950 the wide-scale atmospheric testing of UsefulNotes/NuclearWeapons had significantly altered the ratio of carbon isotopes, which are one of the primary methods of dating fossils.
131	* Platform/{{UNIX}} time keeping uses seconds instead of years, with the 0 second set at midnight on January 1, 1970 GMT.
132	* The Classic[[note]]Pre-Mac OS X[[/note]] Mac OS used January 1904 as its zero point. This year was chosen instead of 1900 in order to simplify the logic of determining if a year is a leap year, since CPU cycles were precious on the early Macs.
133	[[/folder]]

Context Main / YearZero