The internal carotid artery is a major branch of the common carotid artery, supplying several parts of the head with blood, the most important one being the brain. There are two internal carotid arteries in total, one on each side of the neck. They originate from the carotid bifurcation. Each artery is divided into seven segments according to the areas through which it passes. Along its course, the internal carotid artery gives rise to many branches, ultimately dividing into its two terminal ones called the anterior and middle cerebral arteries.