Psychology is the scientific study of human behavior and mental processes. It involves systematically studying topics through defining problems, forming hypotheses, designing methods, implementing methods to gather and analyze data, and making conclusions. Behaviors can be overt and observable or covert and hidden. Psychology aims to describe behaviors, explain behaviors, predict behaviors, and control undesirable behaviors. The five pioneering schools of psychology were structuralism, functionalism, Gestalt approach, behaviorism, and psychoanalysis.