Noun - urban (or suburban import) dweller who goes to all the coolest clubs, listens to the coolest music, is into various aspects of the arts, including but not limited to street art, indie films, street displays, sticker art, etc.... A hipster also must know all the coolest other hipsters. If you have to ask what a hipster is, then you are definitely not a hipster. Hipsters have more music on their ipods then anyone they know, and all the bands are indie or underground.
Q: how many hipsters does it take to screw in a light bulb?
A: What, you don't know?