Defense mechanisms are unconscious psychological strategies brought into play by various entities to cope with reality and to maintain self-image.
This is a psychological attempt made by an individual to their characteristics that they find harmful into their unconsciousness.
Denial is probably one of the best known defense mechanisms, used often to describe situations in which people seem unable to face reality or admit an obvious truth (i.e., "He's in denial.").
Projection is a psychological defense mechanism in which individuals attribute characteristics they find unacceptable in themselves to another person.