The Hipster Handbook
Definition of a Hipster Hipster - One who possesses tastes, social attitudes, and opinions deemed cool by the cool. (Note: it is no longer recommended that one use the term "cool"; a Hipster would instead say "deck.") The Hipster walks among the masses in daily life but is not a part of them and shuns or reduces to kitsch anything held dear by the mainstream. A Hipster ideally possesses no more than 2% body fat.
The Glossary: http://www.hipsterhandbook.com/glossary.html