Peripheral nervous system (pns):

Except for the  brain and the spinal cord,  the  rest of  the network  of  nerves and neurons is included in tha  peripheral nervous system, or PNS for short. This system links the brain andspinal cord to the rest of  the body. Any message that is sent to the brain or from it to the rest of body, travels along the peripheral nerves. The PNS consists of  12 pairs of  individual nerves called cranial nerves,  originating  from the brain hence called cranical nerves (from cranium, the  skull) and the 31 pairs of  spinal nerves that branch off from the spinal cord. Each  spinal nerve splits into  three components  soon after  leaving the spinal cord. One- branch passes to the skin and muscles of the  front of  the body;  a second branch leads to the skin and muscles of  the back; the third branch reaches the  internal organs. The first two branches carry sensory information to the  brain, and carry motor signals  from the brain to the muscles and glands. The  third branch forms the "autowmic  system" which governs actions  of  the internal organs that are mostly involuntary. If  you  look at Fig. again, you would be able to appreciate  the  vast network of  nerves that make up the peripheral nervous system.