You have many kinds of cell involved in your nervous system, from different fast-signalling neurons to various glial cells supporting and shaping the neurons. But you have two major divisions of nervous system. Your peripheral nervous system moves your muscles and senses touch, taste, heat, etc. Your central nervous system is your brain and spine, and puts together information from your senses to control your decisions and behavior. That kind of system happens in 2-sided animals (dogs, fish, you, etc). Radial animals (jellies, sea-stars, etc) have neural nets, but not central and peripheral divisions because their centers are too simple.