The document discusses disability, its dimensions, types and classification. It defines disability as any restriction or lack of ability to perform activities considered normal. Disability has three dimensions - impairments, activity limitations, and participation restrictions. The nine major types of disabilities are described. The document also discusses prevention of disabilities through various approaches like primordial, primary, secondary and tertiary prevention. It describes disability screening and identification, which includes methods, techniques and examinations for early detection. Various screening types and levels are explained. Identification of disabilities can be done through questions, checklists and developmental milestones.