The skeleton gives us our shape and keeps our body upright. Without the bony framework, we would probably have looked like a flabby jellyfish on land, because, after all, one-fifth of our body is water. We differentiate our skeleton into the skull, the body, and the limbs. The first two protect us against injuries from outside, and the limb skeleton primarily takes care of our movement. The bones of the skeleton are joined by ligaments. We move with the help of muscles. Muscles become stiff and ache after a vigorous workout.