Sigmund Freud is often considered the founder of modern psychology. He developed psychoanalysis, a method that emphasizes the importance of the unconscious mind, childhood experiences, and internal conflicts in shaping human behavior. Freud introduced concepts like the id, ego, and superego, which describe the dynamic interplay of different parts of the psyche. Though some of his theories have been criticized and evolved over time, Freud's impact on psychology, psychiatry, and even popular culture is undeniable. His ideas laid the groundwork for many areas of psychological thought and clinical practice, influencing not only mental health but also literature and art.