Activision stirred up the game community when it confirmed that Call of Duty: Black Ops 4 was in the works, set to release later this year. But the announcement actually set off an interesting precedent on the Internet, when some folks complained how the game logo read Black Ops IIII instead of, say, Black Ops IV. (We just say Black Ops 4 to keep it simple, but those folks just keep on pushing.)
Despite arguments coming from both sides, Eurogamer decided to do something about it, and actually got in touch with a British museum to see if Activision's listing of Black Ops IIII in the official game logo is legitimate. Turns out, it actually is.
Both IIII and IV are legitimate Roman numerals, as many people actually used both. In fact, some were even noted to have put both usages in the same historical document.
According to the article, "Often addition (IIII = 4) was preferred to subtraction (IV = 4). The subtraction notation - also called the subtractive notation, which is moderately cooler to say but I'll admit it's a squeaker - was not used exclusively until the 13th century, in fact - and it was not universally adopted in the Roman period. ('Exclusively' is not quite right either, of course - modern watchmakers in particular remain fond of IIII.)"
"And get this, everyone: reading around, I discovered that it has been argued that the subtraction notation was developed after the addition notation, and you can kind of glimpse the reasoning behind this for yourself if you think of the subtraction notation as being, well, a form of shorthand. IV could have followed on from IIII quite naturally because it required fewer characters and was less effort. (You can see this most clearly if you compare 9s: VIIII is a bit of an awkward pain that nobody wants to get stuck in an elevator with; IX is rather dashing.)"
"Bonus fact, because it is Friday: M was never used by the Romans to represent 1000 and only became popular in the 15th century in England. Blammo!"
So there it is. Whether you use Black Ops IIII or Black Ops IV, turns out you're right either way. (Again, we're just going to say Black Ops 4, because what's wrong with general numbers?!)