The nervous system helps signal other body parts to do things. The main part is the brain, which is the head of the body (metaphorically and literally). It sends signals to the nerves to get through to to other parts of the body. The brain consists of the cerebrum, the cerebellum, and the brain stem. The cerebrum is responsible for movement, touch, temperature, vision, hearing, judgement, reasoning, problem-solving, emotions, and learning. The cerebellum is responsible for planning, motor skills posture, balance, coordination, and speech. The brain stem is responsible for breathing, digesting food, and circulating blood. Another very important part of the nervous system is the spinal cord. It is just a big vertical clump of nerves that reaches from the brain stem all the way down to the pelvic area. It is a pathway for signals around the body to get to different places. Think of it a like a "main road" which connects the smaller "roads", (the nerves).