Arteries and veins are the main vascular systems of the body, which are the channels of life and are closely related to the life activities of human beings. The role of arteries and veins is very different: arteries carry the arterial blood to the tissues and capillaries around the body, while veins, on the contrary, return the venous blood from the tissues and capillaries, which is the metabolic waste of the tissues, to the heart and pulmonary arteries and the liver for the exchange of nutrients. Arteries generally have smaller lumen, thicker wall, and stronger pulsation, and the pulsation of arteries can be felt in some superficial parts of the body; while veins generally have larger lumen, thinner wall, and less obvious pulsation, and the veins are superficial compared to arteries, and some greenish-purple stripes can be seen on the body surface are veins.