This document provides an overview of the autonomic nervous system (ANS). It describes that the ANS consists of motor neurons that innervate smooth and cardiac muscle and glands to make adjustments and ensure optimal body support through subconscious control. The ANS differs from the somatic nervous system in its effectors, efferent pathways, and target organ responses. The ANS is divided into the sympathetic and parasympathetic divisions which counterbalance each other. The sympathetic division is involved in the fight or flight response while the parasympathetic performs maintenance functions.