The word "Arthritis" means "joint inflammation." Inflammation is one of the body's natural reactions to disease or injury, and includes swelling, pain, and stiffness. Inflammation that lasts for a very long time or recurs, as in arthritis, can lead to tissue damage.
A joint is where two or more bones come together, such as the hip or knee

Arthritis is a term used to describe a number of painful conditions of the joints and bones.There are over 100 types of arthritis including osteoarthritis, rheumatoid arthritis, and gout affecting young and old alike. The symptoms includes swelling, pain, and stiffness and can affect many parts of the body.