Tears flow from tear glands into your eyes through tiny tear ducts. The tear glands are located under your upper lids, and when stimulated, produce tears to form a thin film over your eyes. Every time you blink the film spreads over your eyes to keep them moist and free of dust and other irritants. Whether you are awake or asleep, happy or sad, this salty fluid is always flowing from the tear glands.

Besides protecting your eyes, the tear glands produce more fluid when your eyes are irritated. These extra tears are called reflex or irritant tears. And, when something makes you happy or sad, your tear glands will produce emotional tears. Tears drain down into two tiny openings on the brim of your upper and lower eyelids at the inner edge of your eyes, which lead to the nasolacrimal tear ducts next to the bridge of your nose. From there, they are channeled into your nasal cavity where they are swallowed or blown out with other nasal fluids. If there are too many tears, they will overflow your lower lid and run down your cheeks this is what happens when we cry!