Crabs are the animals that most people think of when they think of crustaceans. Crabs can be found on land - even in deserts - and down to the greatest depths of the oceans. They come in many different shapes and sizes but always have one pair of chelipeds (claws, pincers or nippers) and four pairs of walking legs. Typically crabs are wider than long and with legs enabling them to run sideways. Many are more or less triangular or spherical and move slowly in all directions. True crabs belong to the infraorder Brachyura and can be divided into as many as 50 families.