Final answer:
Sigmund Freud's theory of personality includes three distinct structures: the id, ego, and superego, which interact with each other to form our personality.
Step-by-step explanation:
Sigmund Freud presented the first comprehensive theory of personality. He proposed that our personality develops from a conflict between our biological aggressive and pleasure-seeking drives and our internal control over these drives. Freud suggested that our personality is composed of three interacting structures: the id, the ego, and the superego. The id contains our basic instinctual drives, the ego balances the id's impulses with the superego's moral ideal, and the superego represents societal rules and ethics.