In humans and other vertebrates, the nervous system is comprised of two main parts: the central nervous systemand the peripheral nervous system.
Central Nervous System
The central nervous system (CNS) contains the brain and spinal cord, and forms the majority of the nervous system. The brain is protected by the thick bones of the skull, and the spinal cord is protected by the vertebrae.
Peripheral Nervous System
The peripheral nervous system (PNS) connects the CNS to limbs and organs. The PNS is divided into the:
Autonomic nervous system
Somatic nervous system
Enteric nervous system