Psychology is the study of behavior and mental processes. Behavior is everything we do that can be directly observed. Mental processes are the thoughts, feelings, and motives that each of us experiences privately but that cannot be observed directly.
When dealing with science, psychology uses systematic methods to observe human behavior and draw conclusions. The goals of psychological science are to describe, predict, and explain behavior. Also, psychologists are often interested in controlling or changing behavior, and they use scientific methods to examine interventions that might help.