In this video, a detailed account of vagus nerve / cranial nerve X is given. Various types of fibers in the vagus nerve i.e., somatic visceral afferent (SVA), somatic visceral efferent (SVE), general somatic afferent (GSA), general visceral efferent (GVE), and the general visceral afferent (GVA) and their respective functions are thoroughly discussed. The innervation of thoracoabdominal viscera by the vagus nerve is particularly elucidated extensively. The clinical correlation at the end provides insight of the manifestations of damage to vagus nerve. 1:06 Fibers in vagus nerve 2:32 GSA fibers 5:48 SVA fibers 7:54 SVE fibers 15:19 Recurrent laryngeal 19:51 GVA fibers 24:31 GVE fibers 25:58 Thoracic and abdominal viscera 39:23 Clinical relevance