Camber refers to the curvature along the length of a snowboard. Camber is important because it affects the way a snowboard reacts on different types of terrain. The most common types of camber in include traditional camber, rocker (or reverse camber), flat camber (or zero camber), and cambered medley (or camber combination).
A board with traditional camber curves such that if it's sitting flat on a hard surface, the middle of the board will be raised off the ground.
This type of camber is meant to maximize edge contact with the snow while turning, thus making it useful for riding hardpack and groomed runs and for high-speed carving.