According to Sigmund Freud, personality has three components - the Id, Ego, and Superego. The Id operates on the pleasure principle, seeking immediate gratification of needs. The Superego develops through socialization and represents a person's conscience based on social norms of right and wrong. The Ego acts as a mediator between the Id and Superego, balancing desires and morality using the reality principle to satisfy needs in a socially appropriate way.