The largest artery in the body is known as our aorter and then we have the arteries followed by smaller arteries known as arterios and finally our capillaries. Now the second type of blood vessel is the vein and if the artery carries blood away from the heart and to the tissues then our veins bring our blood to the heart and away from our tissues and organs. Now most of the veins in the body actually carry deoxygenated blood but there are examples as we'll see in a moment in which veins actually carry oxygenated blood. And just like arteries vary in size we also have a range of different size values for our veins. The largest vein is known as our vena cava. We also have the smaller veins.