The central nervous system is the part of the nervous system that includes the brain and spinal cord. It integrates information it receives from, and coordinates and influences the activity of, all parts of the body.
This is the part of the nervous system outside the CNS. It connects your brain and spinal cord to other areas of your body, like a network cable connecting your CPU to other devices.
These are nerve cells that transmit signals throughout your body. They're like tiny messengers or data packets carrying instructions from your 'CPU' (CNS) to different parts of your 'computer' (body).