Everybody has likely felt anger at one time or another. While particular individuals get angry more often than others and have regular, intense outbursts, others tend to bottle their feelings and then blow up or flare up without warning.  
Anger is a basic human emotion and a natural response to situations beyond our control. There are a lot of things that may set off or contribute to anger, like the actions of another individual, an event, tension, expectations not being met, feeling hurt, contempt, humiliation, embarrassment, jealousy and sorrow.