ADA provides protection from discrimination on the basis of one's disability. According to ADA, a person is disabled if he/she has a mental or physical impairment that substantially limits major activities of life. The policy also provides protection if a person has a history of such disability. In order to get protection through ADA act, a person must have a substantial impairment, or history of such impairment. According to ADA, a substantial impairment is something which affects one's ability to walk, breath, see, hear, learn, work, care and perform manual tasks.