The best explaination of ok I have heard was in science fiction...


Because of the (future ) use of the metric system, the time travelers that went back used the term "0 k" ( zero kilometers) to indicate something that was unused, totally new, or like new. Since the people of the era they visited were using the English system, when they were overheard to say "ok", it was thought to be slang. As the time travelers had set themselves up as upper class ( wealthy) individuals, this soon caught on, and thus...