Anger is an emotional state that varies in intensity from mild irritation to intense fury and rage. Like other emotions, it is accompanied by physiological and biological changes; when you get angry, your heart rate and blood pressure go up, as do the levels of your energy hormones, adrenaline, and non-adrenaline.
Anger can be caused by both external and internal events. You could be angry at a specific person (Such as a co-worker or supervisor) or event (a traffic jam, a cancelled flight), or your anger could be caused by worrying or brooding about your personal problems. Memories of traumatic or enraging events can also trigger angry feelings.