Branch of psychology concerned with solving practical problems of human behaviour by using the findings and methods of psychological science.
motivation , and delinquency were among the first areas of application in the early 20th century. World Wars I and II fostered work on vocational testing, teaching methods, evaluation of attitudes and morale, performance under stress, propaganda and psychological warfare , and rehabilitation. The aviation and aerospace industries were important for the development of engineering psychology, the study of human-machine relationships. Other areas include consumer psychology , school psychology , and community psychology. See also industrial-organizational psychology ; psychometrics .