Having only one term to describe two phenomenon, has weakened people's understanding of anger and their ability to change. Anger often has a negative connotation because people think only of the ineffective or terrifying anger behaviors. As an emotion anger is usually a secondary emotion, not a primary one. That is, another emotion occurs first. This first emotion usually occurs so quickly that it goes unnoticed and unspoken.
Anger tends to emerge when people experience fear, hurt, or become intensely frustrated.
In the face of these emotions humans are designed to become mobilized for action. Anger, the emotion, is the source of physiological arousal to deal with threat, injury or frustration. People under threat often exhibit great feats of strength or courage. For instance, there are numerous anecdotal stories of a parent who lifts a heavy object off their child who is pinned beneath it. This is anger in response to the hurt or fear involved in a threat to one's child.