There's normal weapons, and class-specific weapons, IIRC, like in Diablo 2. As far as ranged weapons go, there's the bow, the crossbow, and the hand-crossbow. Only the hand-crossbow is class-specific to the Demon Hunter.
That said, while most weapons can be equipped by any class, only a select few are really effective in their hands. For the Demon Hunter, it's ranged weaponry.