In this section, we delve into the complex nature of intelligence, defined as an individual's capacity to reason, understand complex ideas, learn from experience, and adapt to environmental changes. We explore individual differences in intelligence, the methods through which psychologists assess these differences, and how cultural norms shape our understanding of what constitutes intelligence. Various theories are presented, including Binet's original studies leading to the intelligence quotient (IQ), Gardner's multiple intelligences, and Sternberg's triarchic theory. The interplay between heredity and environment in determining intelligence is discussed, highlighting that intelligence can manifest diversely based on cultural contexts and personal experiences. Furthermore, the section emphasizes the importance of emotional intelligence and its role in personal and academic success. Through understanding these differences and assessment strategies, psychologists can better support both intellectually gifted individuals and those facing intellectual disabilities.