What's behind anger?

According to Albert Ellis, the most common irrational ideas behind anger are the following.

1. I must do well and win the approval of others for my performances, or else I will rate as a rotten person.

2. Others must treat me considerately and kindly and in precisely the way I want them to treat me.

3. The world (and the people in it) must arrange conditions under which I live, so that I get everything that I want when I want it.

Mark Cosgrove, Counseling for Anger