This document provides an overview of disabilities including definitions, classifications, history, causes and society's role. It defines disability as an interaction between a person's body and their environment according to the WHO. Disability exists on a continuum from mild to severe. The history discusses developments from ancient prosthetics to modern inclusion movements. Causes include genetic, medical and societal factors. Major forms of disability recognized are physical, intellectual, sensory and developmental. The document emphasizes that society often stigmatizes those with disabilities through segregation, shame and viewing them as burdens.