The human skeleton is formed by a framework of bones and their associated cartilage. Most adult human skeletons contain 206 bones, which may be classified in a number of ways. The skeletal system serves many important functions, including the provision of shape and support, protection of internal organs, assistance in movement, storage of minerals and blood cell production. In this first section, an overview of the structure and generation of bone tissue is provided. Further detail can be found in any dedicated human anatomy textbook.