[Image:Struthio camelus in Serengeti crop.jpg|thumb|250px|An
ostrich, the fastest extant biped at 70 km/h]]
Bipedalism is a form of
terrestrial locomotion where an organism
moves by means of its two rear
limbs or
legs. An
animal or
machine that usually moves in a
bipedal manner is known as a
biped , meaning "two feet" (from the
Latin bi for "two" and
ped for "foot"). Types of bipedal movement include
walking,
running, or
hopping.