Bones are the hard structures that make up the skeleton of many animals, including humans. They provide support and shape to the body, allowing us to stand upright and move. Bones are made of a tough material called calcium phosphate, which makes them strong yet lightweight. They also protect vital organs, like the heart and lungs, and store important minerals. In addition to their structural role, bones are alive and constantly changing. Inside some bones, there is a soft tissue called bone marrow, which produces blood cells that help our body fight infections and carry oxygen. Overall, bones are essential for both movement and health.