Study of the psychological processes of children.
The field is sometimes subsumed under developmental psychology . Data are gathered through observation, interviews, tests, and experimental methods. Principal topics include language acquisition and development, motor skills, personality development, and social, emotional, and intellectual growth. The field began to emerge in the late 19th century through the work of G. Stanley Hall and others. In the 20th century the psychoanalysts Anna Freud and Melanie Klein devoted themselves to child psychology, but its most influential figure was Jean Piaget , who described the various stages of childhood learning and characterized the child's perception of himself and the world at each stage. See also school psychology .