This document discusses theories of personality and self-concept and how they affect consumption patterns. It covers several theories of personality including Freudian theory which views personality as consisting of the id, ego, and superego. Trait theory views personality in terms of measurable traits. Self-concept is defined as one's thoughts and feelings about oneself and is influenced by one's actual self and ideal self. Products are chosen that are consistent with one's self-concept and that can help improve self-esteem by closing the gap between actual and ideal selves. Marketers aim to appeal to consumers' traits, self-concepts, and fantasies about their ideal selves to influence product choices.