The field of psychology had its modern origin just over 100 years ago, and yet interest in the field has grown rapidly. Researchers with broad and varied interests have expanded the field, and as a result there are many different subdisciplines. Highlighted here are several key areas of psychology.
Biological psychologists apply biological principles to the study of mental processes and behavior. The field examines the basic biological processes that underlie normal and abnormal behavior at the level of nerves, neurotransmitters, and brain circuitry.

In clinical psychology, science, theory, and clinical knowledge are combined to improve psychological distress or dysfunction, and to promote personal well-being. Clinical and counseling psychology are similar subdisciplines.

Cognitive psychology is the scientific study of how people perceive, remember, think, speak, and solve problems, by exploring internal mental processes in the brain.

Comparative psychology studies the behavior and mental life of non-human animals, like pigeons, cats, and monkeys, with the hopes that it will inform our understanding of humans.

Developmental psychology focuses on the psychological changes of the human mind throughout the life span. Developmental psychologists study infants, the elderly, and every age in between.

Educational psychology studies the cognitive, emotional, and social learning processes in educational settings, while school psychology focuses on treating behavioral and learning problems commonly found in school-age children that may interfere with schoolwork.

Industrial and organizational psychology applies psychological concepts to create efficient behavior in the workplace. For example, they may help find employees wellsuited for certain jobs or design user-friendly products.

Personality psychology explores personality and individual differences in thought and behavior.

Social psychologists study relationships between individuals and groups, and how social situations may influence behavior and cognition.

Evolutionary psychology investigates which psychological traits may be functional adaptations resulting from natural selection.

Quantitative psychology studies the methods and techniques used to measure human traits, the design of research studies, and the analysis of psychological data.

Health psychology focuses on how biology, behavior, and social factors influence health, such as the onset and course of disease, and the prevention of illness.

Sports psychology explores psychological factors that influence involvement and performance in sports. For example, one area of focus is how visualization may enhance performance.

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