A cobra is a venomous snake of family Elapidae, of several genera, but particularly Naja. Cobras generally inhabit tropical and desert regions of Asia and Africa. The cobra's most recognizable feature is its hood, a section of its neck which it can flatten outwards in a threat display. Note that most snakes can flatten their necks to some degree; cobras are only more adept. Cobras come in varying colors from black or dark brown to yellowish white. Elapidae cannot fold their fangs down, as Viperidae can, so their fangs are generally shorter. Most cobras are quite large, reaching on average 1.2–2.5 m (3.9-8.2 ft) long. (wikipedia)