The document provides an introduction to the anatomy of the central nervous system, focusing on the spinal cord. It describes the basic structures and classifications of the nervous system, including the central nervous system (CNS), peripheral nervous system (PNS), sensory and motor divisions, and autonomic nervous system. Key aspects of the spinal cord are discussed, such as its external and internal structures, as well as the organization of gray matter into nuclei and ganglia and white matter into tracts. The roles of neurons and neuroglia are also summarized.