The psychosexual stages are a theory proposed by Sigmund Freud that outlines the development of personality through five distinct phases. Each stage is characterized by the focus of pleasure on different areas of the body, influencing personality traits and behaviors. The stages include the oral, anal, phallic, latency, and genital stages, occurring from infancy to adulthood. Freud believed that unresolved conflicts during any of these stages could lead to fixation, affecting an individual's personality and behavior later in life. For example, fixation at the oral stage might result in dependency issues, while fixation at the phallic stage could lead to problems with authority and relationships.