The document provides an introduction to the nervous system. It discusses that the nervous system is composed of two main divisions: the central nervous system (CNS) containing the brain and spinal cord, and the peripheral nervous system (PNS) containing nerves. Sensory information travels via sensory neurons to the CNS, which integrates the information and sends motor commands via motor neurons. Motor commands can target skeletal muscle through somatic nerves or smooth and cardiac muscle through the autonomic nervous system. Neurons transmit nerve impulses while various neuroglial cells provide structural and nutritional support, including myelinating neurons to increase transmission speed.