Illustration of a human skull. The skull may be divided into the cranium (enclosing the brain), and the face (which includes the lower jaw or mandible). The whole structure comprises 22 seperate bones. The cranium consists of 8 bones connected by immovable joints (sutures): the vault of the cranium is formed by the two frontal and the two parietal bones. All the bones in the skull except the mandible are connected by immovable joints. The skull contains cavities for the nose (nasal cavity) and sockets for the eyes (orbits).