The facial nerve is the seventh cranial nerve, responsible for controlling the muscles of facial expression. It also plays a role in the sense of taste for the anterior two-thirds of the tongue and provides some functions related to salivary and tear glands. This nerve emerges from the brainstem and travels through the skull before branching out to various facial muscles. Damage to the facial nerve can lead to conditions such as Bell's palsy, which causes temporary weakness or paralysis of one side of the face.