Tears are mysterious. We never know when they are going to appear, and often, they evoke emotions that go deep into our inner being. Not long ago, while watching a rerun of one of my all-time favorite ...

You’ve probably tasted your own tears and figured they have salt in them. What you might not realize is that tears contain a lot more than just that — and that they serve some very diverse purposes!

Crying as an expression of emotion appears to be uniquely human behavior. Other animals may tear up because of irritants in their eyes, but only humans shed tears at times of extreme sadness or joy.