Gestures and facial expressions often communicate what words cannot say. Words aren't always genuine, for they can be said as well as they can be blown away with the wind. For this matter, it is in every human being's advantage that there are facial expressions, to expose what words cannot communicate.
Strong feelings and emotions such as sadness, fear, grief, disgust, anger, joy, and especially surprise cannot easily expressed with only the use of words. There is a need for gestures and facial expressions in order to produce the emotions significance.
Facial expressions come naturally to us. We are gifted with them since birth. A newborn baby doesn't learn gestures form his/her parents. Newborns aren't taught how to show pain, but the do, sometimes without even crying or screaming. The gestures they produce correspond their expressions, in this case, screaming or crying. When raising a child, parents tend to condition them to certain behaviors. They teach them what is, and we quote, "right and wrong." A parent accustoms his/her child to certain facial expressions. If a parent displays a look of anger, the child immediately knows he/she has done something bad. If a parent displays a look of content, the child knows he/she has or is doing something that is good, or all right by the parent.
Someone could easily tell what another person is thinking just by looking at his or her gestures. If you were to see someone smiling, automatically you know that the person is happy or something amuses him/her. It's the same if the person were frowning and slouching; you"d automatically know that the person is feeling depressed or sad. It's just the same for expressions of anger, surprise, disgust, or any other expression.
If a person a person were to give an expression or gesture portraying anguish or distress at his or her birthday party, you"d instantly know that there's something wrong with the person.