Anger is caused by blocked goals.
It is a normal emotional response to situations or people who seem to be preventing you from achieving a personal desire or goal. For instance, you may get angry when your parents refuse to allow you to purchase a certain item or tell you to be home earlier than you think is reasonable. They are preventing you from fulfilling your momentary desire to have or do something you want. You can reduce some of your anger by re-evaluating your goals. You'll find that maybe some of your goals are improper.