Sigmund Freud is known as the father of psychoanalysis. He developed this groundbreaking approach to understanding the human mind in the late 19th and early 20th centuries. Freud introduced key concepts such as the unconscious mind, defense mechanisms, and the significance of dreams. He believed that unresolved conflicts from early childhood experiences significantly influenced adult behavior and mental health. His theories sparked substantial debate and led to the establishment of modern psychotherapy practices. Despite criticism and revisions of his ideas over time, Freud's foundational work laid the groundwork for future psychological theories and practices.