The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone, however two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium (braincase) and the viscerocranium that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans, these sensory structures are part of the facial skeleton.

अयं कपालः शरीरस्य किञ्चन अङ्गम् अस्ति । कपालः सम्पूर्णस्य शिरसः अस्थिभागः । कपालस्य कारणतः एव शिरसः वा वदनस्य वा निर्दिष्टः कश्चन आकारः भवति । अयं कपालः आङ्ग्लभाषायां Skull इति उच्यते ।