An appropriate, yet annoying way of saying "newbie" in reference to someone who is an unexperienced and unskilled gamer. Most often used by people who have nothing better to do than play video or computer games for most of their pathetic lives, and are offended by the overconfidence of unproven new comers. "Noob" is a popular word in gamer language. In some instances, exceptionally bad players may be referred to as "boon" or "nub" (but only in rare, extreme cases)
(after getting killed) "you stupid noob!"
or "KTHX PWNED, STFY GFY... NOOB."
or "Damn, AYOUNG is a fucking NOOB dude"