Rheumatoid arthritis is a chronic inflammatory illness. It is an autoimmune disease in which the immune system attacks normal tissue components as if they are invading pathogens. The inflammation associated with rheumatoid arthritis primarily attacks the linings of the joints. It is treated by taking rest, splinting of affected joints and exercise programs. Good nutrition is also very important. It is important because patients with a more advanced disease often experience anemia and weight loss. Medication is the best way to control pain and stiffness and reduce the risk of joint deformity.