This document discusses different perspectives on what constitutes abnormal behavior and how it has been defined and treated throughout history. It explores statistical, social, and functional definitions of abnormality. Historically, abnormality was viewed through supernatural lenses and treated with exorcisms or torture. Later, Hippocrates and Galen proposed biological causes, like humoral imbalances. In the 19th century, psychiatry emerged treating mental illness as physical conditions, focusing on hospitalization. Treatments have included shock therapies, brain surgery, and modern psychotropic drugs.