The document summarizes the structure and function of the nervous system. It describes the nervous system as having two main divisions: the central nervous system (CNS), composed of the brain and spinal cord, and the peripheral nervous system (PNS), which branches out from the CNS. It then discusses the key components of the CNS, including the forebrain, midbrain, and hindbrain, and provides details about neurons, synapses, and neurotransmitters.