John Wilkes Booth was the son of prominent, wealthy actors. He, too, became an actor and was so popular, he was one of the first to have his clothes ripped off by fans. Hulton Archive/Getty hide caption
Psychology is the systematic investigation of the human mind, including behavior and cognition. It thus encompasses both normal and abnormal behavior. On the other hand, psychiatry is a branch of medicine dealing with mental illness.
A psychologist and a psychiatrist are often confused as having the same meaning. While both study the brain, emotions, feelings and thoughts, there is a distinct difference between the two fields of study. The primary differences between the two fields is mainly the education requirements, the specific training, practice and salary.