In Freud's structural model of personality: the Id (unconscious, pleasure principle — drives and impulses), the Ego (reality principle — mediates between id and reality), and the Superego (the moral and ethical conscience — internalized societal rules and values, includes the conscience and ego-ideal). The superego develops around age 5–6 through the resolution of the Oedipus/Electra complex. Libido is psychosexual energy, not a structural component.