Invalidity

Disability is an impairment that may be cognitive, developmental, intellectual, mental, physical, sensory, or some combination of these. It substantially affects a person's life activities and may be present from birth or occur during a person's lifetime.

Disabilities is an umbrella term, covering impairments, activity limitations, and participation restrictions. An impairment is a problem in body function or structure; an activity limitation is a difficulty encountered by an individual in executing a task or action; while a participation restriction is a problem experienced by an individual in involvement in life situations. Disability is thus not just a health problem. It is a complex phenomenon, reflecting the interaction between features of a person’s body and features of the society in which he or she lives.

Disability is a contested concept, with different meanings for different communities. It may be used to refer to physical or mental attributes that some institutions, particularly medicine, view as needing to be fixed (the medical model). It may refer to limitations imposed on people by the constraints of an ableist society (the social model). Or the term may serve to refer to the identity of people with disabilities.

The discussion over disability's definition arose out of disability activism in the U.S. and U.K. in the 1970s, which challenged how the medical concept of disability dominated perception and discourse about disabilities. Debates about proper terminology and their implied politics continue in disability communities and the academic field of disability studies. In some countries, the law requires that disabilities are documented by a healthcare provider in order to assess qualifications for disability benefits.

Contemporary understandings of disability derive from concepts that arose during the West's scientific Enlightenment; prior to the Enlightenment, physical differences were viewed through a different lens.

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Wikipedia