What makes up peripheral nervous system?

Peripheral nerves...: The peripheral 'wiring schematic' begins at the nerve roots exiting the spine (at the anterior horn cell, to be specific), which then travel through a plexus (one on each side of the pelvis, and one under each collarbone), which emerge as peripheral nerves into the arms & legs, terminating at the junction with an organ (such as muscle or skin). Head and neck nerves differ slightly.