Some people show themselves as a different person in front of people. In worries of what those people might think about them. This is normally because the person is nervous embarresed or just plain stuck up and everything along those lines. This is called character. A good example of character is When you are by yourself you have the urges to cut yourself in certain areas to relief pain or stress of tradgic events or conflict. When you are out in public you try to hide this as much as possible because of the embarresment and worries with what people think. This is an example of character. When you act like someone you are not to protect your character.
Some people are so intimate about there self character they will do crazy things to protect who they really are on the inside.