It's one of the first things we do when we emerge from the womb. As babies, we haven't yet developed the ability to talk. Still, we instinctively know a very effective way to get our point across. Crying is our first way to communicate our needs to other human beings. Fortunately for parents, talking starts taking the place of crying as we age and mature, at least for the most part!

Our eyes need to stay lubricated to function well. Fortunately, we have a mechanism for that, and it involves moisture. Our tear ducts secrete a liquid that not only moistens our eyes but contains antibacterial properties to keep our eyes clean. These special tears also create a shield against irritants and other residue that can interfere with your vision.

Even a tiny speck of dust in your eye hurts. Irritants in your eye not only annoy, but they can also potentially damage your vision. That's why your body turns on the tears to help. Reflex tears are produced in reaction to anything in your eyes that shouldn't be there. Once the sediment is flushed from your eyes, the tears should stop, and you can put away the handkerchief.

Ever notice how you sometimes cry when you cough? People's eyes can also tear up while choking or laughing. That's because these extreme reactions in the body trigger reflexive actions. Your body senses a problem and works overtime to expel any irritants and pathogens that can harm you. Even though you may have nothing in your eyes, your body still produces tears to flush out any problems that might be hiding there to keep you protected.

Sadness is most associated with the appearance of tears, but anger, happiness, frustration and even joy can evoke crying. This expression of emotion comes naturally to all people and is thought to have a soothing effect both physically and mentally. After a good cry, the body is in a calmer state, and your emotions tend to be better regulated. Crying is considered healthy, so don't be afraid to let it all out once in a while.

We've all been there. As soon as you cut into an onion, that strong smell hits your nose, right before an unpleasant burning sensation overwhelms both eyes. Let the tears begin! Onions release a chemical called syn-propanethial-S-oxide. This chemical stimulates glands in your eyes, causing them to tear up. Fortunately, the reaction is short-lived. A little distance between you and this raw veggie will help quell your tears quickly.

We all struggle with anxiety at times. It can put the body under enormous stress and make it difficult to regulate emotions. This is why, after a rough day, you may "lose it" and break down in tears. Crying can help release pent-up emotions as well as stress in the body, thereby eliminating anxiety or decreasing it to a more manageable level.

Ever notice after a big race that your eyes are running almost as much as you just were? Irritants from outside can enter your eyes during physical exertion. Sweat can also enter your eyes, causing irritation, which inevitably leads to tears. Wearing safety glasses during a workout can help shield your eyes from outside elements that can cause them to water.

You just stubbed your toe. Really hard. After a few yelps of pain, you're starting to feel better, which is why you're surprised by the tears streaming down your face. Tears can form in response to pain even if it's occurring about as far away from your eyes as possible. All your body knows is that something triggered a lot of pain. You may have an extreme emotional response to that sudden physical stress and cry. Even if you're not emotionally stressed, your body will protect all the vulnerable parts of your body, such as your eyes. Thus, tears will form to flush out your eyes and safeguard them from whatever it was that injured that other part of your body.