The Demon Hunter is the ranged attack class. They specialize in bows and crossbows, which they supplement with numerous ranged attacks, traps of various types, and even a few melee range skills. They are the only class able to wield hand crossbows, as well as the off-hand quivers.
You can find additional information regarding the demon hunter at http://us.battle.net/d3/en/class/demon-hunter/. Please keep questions tagged diablo-3-demon-hunter to questions specifically about the demon hunter class such as their skills, traits and equipment.