The main differences between arteries and veins are the following: first, the walls of veins are thinner while the walls of arteries are thicker. Secondly, arteries are deeper and are the main blood vessels supplying the limbs, while veins are the return vessels in a more superficial location. Thirdly, arteries have pulsation and can often be palpated, while veins have no pulsation. Fourthly, the venous blood flowing in the veins is venous blood, which has less oxygen and nutrients and is dark red in color, while the arteries are mainly arterial blood, which is rich in oxygen and nutrients and is bright red in color. Fifth, the main function is also different, the artery is the blood from the heart, through the artery supply distal for nutrients and oxygen transport, and then through the vein back to the heart after completing the exchange, to complete the whole cycle.