Grave's disease is an autoimmune disorder in which the immune cells attack the healthy tissues. There is an attack on the muscles and the soft tissues of the eye. Due to the attack of the lymphocytes on the eye tissues, there is redness, swelling and pain in the eye. The muscles are damaged and they lose their capability of stretching the muscle fibres. This causes the eye ball to protrude in the outer direction. The result is that the eye of the affected person looks like bulging and protruding outwards which gives the stairing appearance.