Originally Posted by CielDuMatin
OK is the official state abbreviation for Oklahoma. Known to most living in the USA and since this is a Norther America board, probably a decent assumption that folks would get it.
OKC = Oklahoma City, the capital of the state.
I live in the North-Eastern US and am originally from Europe - wasn't confusing to me at all.
OKC is also the abbreviation used for OK Cupid, reffering to the thread "last message on OKC"