In many comments, I have seen the word 'OP', and I have inferred that this refers to the asker of the question. What I want to know is why OP means what it does. Is it an abbreviation? Is it just called that because someone started calling it that?
There are various contexts for "OP", to be honest... The most common context is Original Poster, in this way it's used on forums.
The most popular is OverPowered, in which it's used to describe something that's just THAT powerful... like the BFG 9000 in Doom.
The last, that I know of, is OPerator, used on multiplayer games to denote admins, moderators, or the server owner. This context is, undeniably, the most powerful, as such people could easily ban you for doing dumb things, like griefing, trolling or hacking.