The internal carotid artery is a major blood vessel that supplies oxygenated blood to the brain. It branches off from the common carotid artery, which divides into the internal and external carotid arteries in the neck. The internal carotid artery travels upward through the neck and enters the skull, where it further divides into smaller arteries that nourish different parts of the brain. This artery is crucial for brain function, as it provides blood to areas responsible for vital processes such as thinking, movement, and sensation. Blockages or narrowing of the internal carotid artery can lead to serious conditions like a stroke or transient ischemic attack (TIA).