Which bones was formed by the fusion of several bones?

The sacrum is formed by the fusion of five vertebrae, while the coccyx, or tailbone, consists of three to five fused vertebrae. Additionally, the sternum is formed from three parts—the manubrium, body, and xiphoid process—though these are not individual bones fused together in the same way as the sacrum and coccyx. These fused structures provide stability and support to the skeletal system.