This document discusses individual differences and personality traits. It begins by defining individual differences as the unique qualities that distinguish one person from another. It then explores several types of individual differences, including differences in physique, intelligence, attitudes, aptitudes, interests, achievements, and personality.
The document also discusses factors that influence individual differences, such as heredity, environment, and psychological factors. It explains the complementary roles of heredity and environment in shaping a person's growth and development. Additionally, the concepts of personality, personality traits, and theories of personality like trait theory are introduced. Specifically, theories by Gordon Allport, Raymond Cattell, and the Big Five model of personality traits are summarized.