The peripheral nervous system is a network of nerves that branch out from the spinal cord and extend to all parts of the body. It is responsible for transmitting sensory information from the body to the central nervous system (brain and spinal cord) and for sending motor commands from the central nervous system to the muscles and glands. The peripheral nervous system includes both sensory nerves (which carry information from the body to the brain) and motor nerves (which carry commands from the brain to the muscles).