The ulnar artery is a major blood vessel in the forearm that supplies oxygenated blood to the hand and forearm. It branches off from the brachial artery, which is the main artery of the upper arm. The ulnar artery runs along the inner side of the forearm and is important for the circulation of blood to the ulnar side of the hand. As it approaches the wrist, the ulnar artery gives rise to several branches, including the superficial palmar arch, which supplies blood to the palm. It also contributes to the blood supply of the fingers, ensuring that the tissues receive the necessary nutrients and oxygen for proper function.