What are the major structures of the bones and their respective subcategories?

The major structures of bones include the diaphysis (the long shaft), epiphysis (the ends of the bone), and metaphysis (the region between diaphysis and epiphysis). Bones are categorized into two main types: compact bone, which is dense and forms the outer layer, and spongy bone, which is porous and found mainly in the interior. Additionally, bones are classified based on their shape into long, short, flat, and irregular bones. Each type has unique functions and structural characteristics suited to their roles in the body.