Personality Psychology is a branch of psychology focused on the study of human personality and its variations among individuals. It aims to understand the psychological processes and traits that constitute personality, investigate individual differences, and explore commonalities in human nature. Below are some of the major theories and figures in personality psychology:

1. Psychoanalytic Theory
   • Theorist/Contributor: Sigmund Freud
   • Description: Freud’s psychoanalytic theory suggests that personality is formed through conflicts among three fundamental structures of the human mind: the id (instinctual desires), the ego (realistic mediator between desires and reality), and the superego (moral conscience).
2. Individual Psychology
   • Theorist/Contributor: Alfred Adler
   • Description: Adler proposed that individuals are primarily motivated by a striving for superiority and the desire to belong and feel significant within their social context.
3. Analytical Psychology
   • Theorist/Contributor: Carl Jung
   • Description: Jung’s theory encompasses concepts such as the persona, shadow, anima/animus, and self-actualization. He also introduced the idea of the collective unconscious and archetypes.
4. Person-Centered Theory
   • Theorist/Contributor: Carl Rogers
   • Description: Rogers believed in the inherent goodness of people and emphasized the importance of the self-concept. He posited that individuals have an actualizing tendency, or an innate drive towards personal growth.
5. Hierarchy of Needs
   • Theorist/Contributor: Abraham Maslow
   • Description: Maslow proposed that individuals are motivated by a hierarchy of needs. At the base are basic physiological needs, while at the top is self-actualization, the pursuit of personal growth and fulfillment.
6. Trait Theory
   • Theorists/Contributors: Gordon Allport, Raymond Cattell, and Hans Eysenck
   • Description: Trait theorists focus on identifying and measuring individual personality traits. Allport emphasized the uniqueness of the individual, Cattell focused on 16 personality factors, and Eysenck focused primarily on three traits: extraversion, neuroticism, and psychoticism.
7. Social Cognitive Theory
   • Theorist/Contributor: Albert Bandura
   • Description: Bandura’s theory integrates cognitive, behavioral, and environmental influences to explain the development of personality. He emphasized the concept of self-efficacy and the role of observational learning.
8. Biological Theories of Personality
   • Theorists/Contributors: Hans Eysenck, Jeffrey Alan Gray
   • Description: These theories emphasize the role of genetic and biological processes in personality development. Eysenck, for instance, believed that traits are influenced by genetic factors.
9. Five-Factor Model (The “Big Five”)
   • Theorists/Contributors: Robert McCrae and Paul Costa
   • Description: The Five-Factor Model proposes that personality is comprised of five major traits: openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism (OCEAN).
10. Narrative Identity
    • Theorist/Contributor: Dan P. McAdams
    • Description: This theory focuses on the idea that individuals create narratives or life stories that give meaning and coherence to their lives, integrating their experiences and understanding of self over time.
11. Object Relations Theory
    • Theorists/Contributors: Melanie Klein, Donald Winnicott, and others
    • Description: A psychoanalytic theory that places emphasis on interpersonal relations, primarily in the family and especially between mother and child. It considers how these relations affect the individual’s psychological development and personality.

These theories and contributors have played a significant role in shaping the field of personality psychology and have led to a deeper understanding of the complexities of human personality.