Tear drops are made by the lacrimal glands, which sit just above each eye (and slightly to the side). Tears are made of mainly water, but also contain some oils, mucus and some enzymes. The tears are secreted over the eye in a thin layer and keep the surface of the eyeball wet. This is happening constantly and the tears drain through little tiny holes in the inside of your eyelids and then into a tube that connects to your nose! Now, if you are actually crying, tear production increases A LOT and you end up with tears spilling over onto your cheeks and a very runny nose!
Did you know that some scientists have investigated tears and found out that they are actually made up of slightly different stuff depending on whether you are crying through happiness, sadness or pain? How amazing is that?!