Parasympathetic nervous system:

Watch this 2-Minute Neuroscience video to learn more about the divisions of the nervous system.

a subdivision of the autonomic nervous system, the parasympathetic nervous is generally involved in unconscious processes that are emphasized more during times of rest (as opposed to being in a high-stress or emergency situation). These include things like digestion, sexual arousal, urination, etc. Contrast with sympathetic nervous system.