History Main / UnInstallment

* Upon announcing the transition from the Julian to the Gregorian Calendar in 1582, Pope Gregory XIII declared that the day following October 4 of that year would be October 15, essentially meaning that the days 5-14 October, 1582 never existed. This was necessary because the problem with the Julian calendar was that its average year was too long, causing the calendar to slowly fall behind the seasons, so skipping these 10 days was needed to correct this. While Catholic countries adopted the reform immediately, [[UsefulNotes/TheProtestantReformation Protestant]] and Usefulnotes/{{Orthodox|Christianity}} countries hesitated to do the same but eventually made the switch, so the missing days vary from country to country. For instance, Great Britian finally switched in 1752, so most calendars produced in the Anglosphere will omit the dates of 3-13 September 1752, and Russia didn't adopt the new calendar until the start of Soviet era, so they skipped the dates of 1–13 February 1918.

* The numbering of the UsefulNotes/UltimateFightingChampionship's flagship (mostly) PPV events have several discrepancies. At the beginning of the promotion's life, two Ultimate Ultimate cards and their first shows in Japan and Brazil were treated as stand-alone events outside of the chronology (later UFC trips to Japan and Brazil were regularly numbered shows). Later on, UFC 37.5 was thrown together to accompany the organization's first basic cable deal with Fox Sports Net, as one of the matches from the show later appeared in its entirety on ''The Best Damn Sports Show Period'', the first ever MMA match to appear on free TV. A decade later, after the Zuffa buyout had launched the organization into prominence in the sports world, UFC 151 was canceled after its main event was abandoned due to injury. It was decided that the organization would move on to UFC 152 as if the previous event had happened, a practice that would be repeated with with [=UFCs=] 176 and 233 after their main events fell apart. (The flagship numbering does not include the company's expansion into Fight Nights and other lesser events held on basic cable, broadcast or streaming held since 2005, nor does it include live ''Series/TheUltimateFighter'' finale cards, but it does include several international events on cable or streaming scheduled earlier than the traditional 10 PM Eastern Time start in the U.S.)

* The numbering of the UsefulNotes/UltimateFightingChampionship's flagship (mostly) PPV events have several discrepancies. At the beginning of the promotion's life, two Ultimate Ultimate cards and their first shows in Japan and Brazil were treated as stand-alone events outside of the chronology (later UFC trips to Japan and Brazil were regularly numbered shows). Later on, UFC 37.5 was thrown together to accompany the organization's first basic cable deal with Fox Sports Net, as one of the matches from the show later appeared in its entirety on ''The Best Damn Sports Show Period'', the first ever MMA match to appear on free TV. A decade later, after the Zuffa buyout had launched the organization into prominence in the sports world, UFC 151 was canceled after its main event was abandoned due to injury. It was decided that the organization would move to UFC 152 as if the previous event had happened, a practice that would be repeated with with [=UFCs=] 176 and 233 after their main events fell apart for similar reasons. (The flagship numbering does not include the company's expansion into Fight Nights and other lesser events held on basic cable, broadcast or streaming held since 2005, nor does it include live ''Series/TheUltimateFighter'' finale cards, but it does include several international events on cable or streaming scheduled earlier than the traditional 10 PM Eastern Time start in the U.S.)

* The numbering of the UsefulNotes/UltimateFightingChampionship's flagship (mostly) PPV events have several discrepancies. At the beginning of the promotion's life, two Ultimate Ultimate cards and their first shows in Japan and Brazil were treated as stand-alone events outside of the chronology (later UFC Japan and Brazil events were regular numbered shows). Later on, UFC 37.5 was thrown together to accompany the organization's first basic cable deal with Fox Sports Net, as one of the matches from the show later appeared in its entirety on ''The Best Damn Sports Show Period'', the first ever MMA match to appear on free TV. A decade later, after the Zuffa buyout had launched the organization into prominence in the sports world, UFC 151 was canceled after its main event was abandoned due to injury. It was decided that the organization would move to UFC 152 as if the previous event had happened, a practice that would be repeated with with [=UFCs=] 176 and 233 after their main events fell apart for similar reasons. (The flagship numbering does not include the company's expansion into Fight Nights and other lesser events held on basic cable, broadcast or streaming held since 2005, nor does it include live ''Series/TheUltimateFighter'' finale cards, but it does include several international events on cable or streaming scheduled earlier than the traditional 10 PM Eastern Time start in the U.S.)

** A similar situation caused the lettered streets in Washington DC to skip "J". At the time Pierre L'Enfant designed the city grid, "I" and "J" were often treated as interchangeable, and "J" was often written/printed with only a slight bit of curvature to distinguish it from "I".

* ''ComicBook/{{Supreme}}'': The original series was deliberately identified in its indica (and on the first issue's cover) as "''Supreme'' volume 2", as it featured the title character returning to Earth after fifty years' absence. Series creator Creator/RobLiefeld wanted to eventually make a "volume 1" that would cover Supreme's exploits during World War II – this never ended up happening, with the glimpses of Supreme's [[UsefulNotes/TheGoldenAgeOfComicBooks Golden Age]] adventures being limited to occasional flashback stories.

* [[https://www.youtube.com/watch?v=JzS96auqau0 EVO Moment #37]], the legendary footage from [[UsefulNotes/FightingGameCommunity EVO]] 2004, where Diago Umehara makes an insane comeback against Justin Wong in ''[[VideoGame/StreetFighterIII Street Fighter III: Third Strike]]'', which included him fully parrying Chun-Li's [[RapidFireFisticuffs Super]]. If you were wondering about where the footage of EVO Moment #1 to 36 are, there aren't any. The person who uploaded the original video gave the video title a random number, part of it as a marketing ploy to say there were a lot of great moments in EVO.

* An accidental case of this occurred in ''VideoGame/{{Minecraft}}'' during its early days. [[https://minecraft.fandom.com/wiki/Java_Edition_Classic_0.25_03_SURVIVAL_TEST#Trivia The 0.25_04 SURVIVAL TEST version of the game never existed]], but a user mistakenly changed the version on the wiki to 0.25_04. This lead Notch to believe that it was the current update, so he called the next update 0.25_05 SURVIVAL TEST.

* {{Music/ABC}}'s first album ''The Lexicon Of Love'' contained "The Look Of Love (Part One)" and "The Look Of Love (Part Four)". The song DOES have Parts 2 and 3, but they were only included on its 12" single.

* Music/BobMarley And The Wailers' early album ''Soul Revolution Part II'' was titled as such as it was the follow up to ''Soul Rebels'' (which was the first album recorded for Lee "Scratch" Perry [who compiled both of them] and thus "Part I'"). It is often mistaken for the title of the album's dub version, which was actually called ''Upsetter Revolution Rhythm''. The confusion was not helped by the fact that, due to his debts at the time, Perry packaged some copies of the dub album in the vocal album's sleeve. When Trojan reissued both the vocal and dub albums together in 1988, they called the set ''Soul Revolution 1 & 2'', though later reissues restored the original cover and title.

[[folder:Mythology & Religion]]
* This even happens in Literature/TheBible. In the New Testament Letters, St Paul speaks approvingly of an Old Testament prophet called Enoch and warmly recommends the book of Enoch the Prophet as a religious work the Christian should read so as to broaden their wisdom and get a deeper understanding of their faith. Now go to the Old Testament. It is only a book in the Orthodox Tewahedo tradition. Outside of Ethiopia and Eritrea, there are a few scattered references to a great Prophet called Enoch, by inference in the next division down from Moses -- but no book of that name.
[[/folder]]