You'd probably rather have David Banner over for dinner than the Incredible Hulk. A raging green monster just isn't the kind of guy with whom you want to make conversation. Why not? Because most people see anger as a negative emotion, and angry people as unpleasant. But it doesn't have to be that way. In fact, anger can be good.
How you express your anger is important. Being passive-aggressive and writing a nasty note, for example, doesn't help. But if you sit down with a friend and talk about why you're ticked off and what the other person can do to assuage your feelings, it can actually help your relationship. You identify weak spots and breakdowns in communication and work to correct them.
Trying to suppress your anger and not dealing with it can lead to depression, and uncontrolled anger can cause stress and violence. At its most basic, anger acts as a warning sign to let you know that something's wrong and you need to fix it. The Civil Rights Movement never would have happened had it not been for the righteous anger of a group of people.
And although anger does affect your thinking, it doesn't necessarily cloud your judgment. As an emotion, it's actually more useful than fear and can even enhance your ability to compare the strength of one argument against another. Learn how in Can getting angry be good for you?