The nervous system is a complex network that coordinates the activities of the body. It consists of two main parts: the central nervous system (CNS), which includes the brain and spinal cord, and the peripheral nervous system (PNS), which connects the CNS to the rest of the body. The nervous system is responsible for processing sensory information, controlling movements, and regulating bodily functions. Nerve cells, or neurons, are the basic building blocks of the nervous system. They transmit signals through electrical impulses and chemical messengers called neurotransmitters. The nervous system plays a crucial role in responding to stimuli, maintaining homeostasis, and enabling communication between different body parts.