Fibromyalgia is a syndrome characterized by chronic widespread pain, stiffness, and tenderness in the muscles and joints without signs of inflammation. It predominantly affects women between 35-55 years old and causes significant pain and fatigue that interferes with daily activities. While the exact cause is unknown, fibromyalgia is diagnosed by identifying tender points on the body and treatment focuses on managing symptoms through exercise, stress reduction, medications, and alternative therapies as there is no cure.