| Term | Definition |
| Psychology | the scientific study of behavior and mental processes |
| Positive Psychology | the study of happiness, optimism, human strengths, and so forth |
| Biological psychologists | psychologists that study the biological factors underlying our behavior |
| Developmental psychologists | psychologists that explore the causes and effects of changes in behavior and mental processes over the life span |
| Cognitive Psychologists | psychologists that study processes underlying perception, motivation, emotion, memory, problem solving, and other aspects of human thought |
| Engineering psychologists | psychologists that study human factors in the use of equipment and work to design better versions of that equipment |
| Personality Psychologists | psychologists that study the qualities that make people unique and explore relationships among personality characteristics, behavior, and mental processes |
| Clinical psychologists | psychologists that seek to understand the origins of behavior disorders and to help people deal with disorders |
| Community Psychologists | psychologists that provide psychological services to people who often do not seek help and work to prevent disorders by trying to lessen stresses such as poverty |
| Health Psychologists | psychologists that study the relation between behavior and health and work to promote healthy lifestyles |
| Educational Psychologists | psychologists that investigate ways to improve student learning |
| School Psychologists | psychologists that assess students' abilities and provide assistance when needed |
| Social Psychologists | psychologists that focus on how people affect others' behavior and thinking |
| Industrial-organizational psychologists | psychologists that are interested in factors affecting work productivity and satisfaction, such as employee motivation and how to develop positive organizational behavior |
| Quantitative Psychologists | psychologists that are interested in developing and using statistical tools to analyze data relevant to human behavior and mental process |
| Biological Approach | According to this approach, physiological factors determine behavior and mental processes |
| Evolutionary Approach | Approach that states behavior results from evolution through natural selection |
| Psychodynamic Approach | Approach that states that behavior reflects unconscious internal conflict between inherited instincts and society's behavioral rules |
| Behavioral Approach | Approach that emphasizes learning in explaining behavior |
| Cognitive Approach | According to this approach, behavior is a result of information processing, such as perception, memory, thought, judgment, and decision making |
| Humanistic Approach | According to this approach, people choose how to behave based on their perceptions of the world to grow toward their unique potential |
| Culture | the accumulation of values, religious belief, and so forth from a specific social group |