A group of people that embrace everything considered "unique" for the sake of being "unique". Drinks chai most of the time and thinks they know everything about Art because they know a few works by Andy Warhol. They usually goto clubs that is in the middle of nowhere because they don't play mainstream music and circle jerk about the fact that they are the only ones that know a particular band and how everyone else in the world is a conformist.
Their favorite movies consist of mostly anything by Wes Anderson and any B-movies or other independent films that hasn't been poisoned by the corporate Hollywood, or so they would have you believe. Oh, and they think Bruce Campbell is the best actor in the universe.
Hipsters also like to think they are Buddhist despite the fact that they know nothing about it, and to top that off they are usually vegan. They like anything retro and vintage, especially anything to do with the 8-bit generation of video gaming when in reality all they know about video games is Pacman and Super Mario.
They like to spend their time on blogs to an invisible audience about their fashion statements and writing reviews of indie music albums and the occasional rant about how their life sucks because their local thrift store isn't open on sundays anymore. Yeah, tell that to the starving AIDS-ridden african kid dying on the other side of the world, dumbass. Perhaps you'd like to trade places?
Hipsters also like to think they are environmentally-aware and join facebook/myspace groups that supposedly help fight global warming just because they just reached 200 members (and still counting!).
In a nutshell, just a bunch of fake pompous douchebags that like to think they are unique because they like things that no one has heard of.
Douchebag Hipster kid: My favorite artist is Andy Warhol.
Normal person: Oh really? what year was he born?
Douchebag Hipster kid: I don't know... (changes conversation)