[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.