An artery carries blood away from the heart. The blood is oxygenated with the exception of the pulmonary and umbilical artery. The vessel must cope with high pressure demands and therefore has thick, elastic walls. On the other hand, veins carry blood towards the heart, which is usually deoxygenated. They are thinner vessles compared to arteries and contain vlaves which prevent backward blood flow. Veins are also usually more superficial compared to arteries.