The bones of the cranium are classified as flat bones.
Flat bones are typically thin, flattened, and usually curved. They provide protection to internal organs and also serve as a base for muscle attachment. The cranium, which forms the protective shell around the brain, is made up of several flat bones that are fused together. These bones include the frontal bone, parietal bones, occipital bone, temporal bones, sphenoid bone, and ethmoid bone.
Flat bones are different from long bones (like the femur), short bones (like the carpals in the wrist), round bones (which are not a standard classification), and irregular bones (like the vertebrae). The classification of bones is based on their shape and structure, and the flat bones of the cranium are specifically designed to protect the brain while providing a large surface area for muscle attachment.