Impairment is defined as any loss or abnormality of psychological, physiological,or anatomical structure or function (loss of leg) Disability defined as lack of ability of an individual to do his routine activity Disease defined as a condition in which body health is impaired, a depaure from a state of health, an alteration of human body interupting the performance of vital functions Handicap defined as a disadvantage for a given individual,resulting from an impairment or disability , that limits or prevents the fulfilement of a role that is normal for that individual ref ;(page no;44) 23rd edition of PARK&;s textbook of Preventive and Social medicine