The human skeleton is the frame of the body. It gives our body its shape. It is made of bones. An adult person has 206 bones. Babies have more bones, but some bones join together as they grow. The main job of the skeleton is support. It helps us to stand and sit. Without a skeleton, our bodies would be soft, like a jellyfish. The skeleton also protects important organs. For example, the skull is a hard bone that protects the brain. The ribs protect the heart and lungs. Bones are strong because they contain a special mineral called calcium. This mineral helps keep the bones hard and healthy. Regular exercise and good food help our skeleton stay strong.