The subclavian artery is a large blood vessel that originates from the aorta and supplies oxygenated blood to the upper limbs, neck, and chest wall. It branches out into various arteries, including the vertebral artery, which supplies blood to the brain, and the axillary artery, which provides blood to the shoulder and arm. The subclavian artery is essential for maintaining proper blood flow and nourishment to the upper body structures.