It's different than in the UK/US. We'd say "How are you?" often as a throw-away phrase rather than an actual question. If you ask お元気ですか (ogenki desu ka) in Japan often then it's likely to make people think that you're worried about their general health. Also note that the honorific お makes it slightly more formal or polite.
Sorry for the late reply Ronin. It's as typical as saying "How are you?" in English. You don't say that do you? You probably say.... "Hey man" or "What's up?" or "What's going on?" or "Shup Biotch?" lol