This document provides an introduction and overview of psychology. It defines psychology as the scientific study of behavior and mental processes. The document then outlines the history and branches of psychology. The main branches discussed are pure psychology, which includes general, abnormal, social, physiological, parapsychology, and developmental psychology. Applied psychology is also discussed and includes educational, clinical, industrial, legal, and military psychology. Each branch is briefly defined. The document aims to give a broad introduction to the key areas and definitions within the field of psychology.