The primary role of the autonomic nervous system is to regulate involuntary bodily functions, such as heart rate, digestion, and respiration. It operates automatically, without conscious control, and is divided into two main branches: the sympathetic and parasympathetic systems. The sympathetic system prepares the body for “fight or flight” responses during stress, while the parasympathetic system promotes “rest and digest” functions, conserving energy and facilitating recovery. This balance between the two branches is crucial for maintaining homeostasis in the body.