There is cognitive psychology, which focuses on the mind and how thought processes occur. Behavioral psychology concentrates on human behavior and how people act and react to situations. Physiological psychology focuses on the physiological outcomes of the thought processes, such as a faster heart rate when you experience anxiety.
Developmental psychology concentrates on how the human grows and develops.
Group interaction and social problems are the center of social psychology. Testing methods, experiments, and statistics are covered in experimental psychology. Forensic psychology deals with criminals and criminal patterns and thought processes. These are just a few areas of psychology. Industrial and Organizational psychology is a more recent field of psychology.