The aim of this lecture is to present on Nervous System. By this lecture you can understand the transmission of impulses from senses to central nervous system and back to muscles; the reflex action and the pathway of the reflex arc; the function of reflex response and the role of the central nervous system. The nervous system has two main subdivisions: the somatic, or voluntary, component; and the autonomic, or involuntary, component. Here briefly present on three main types of nerve cells: sensory neurone; relay neurone and motor neurone.