Juvenile idiopathic arthritis (JIA), formerly known as juvenile rheumatoid arthritis, is the most common chronic rheumatic disease in children under the age of 16. It is characterized by persistent joint inflammation of unknown cause, leading to joint pain, stiffness, swelling, and potential long-term complications. Understanding the causes, symptoms, diagnosis, treatment, and management of juvenile idiopathic arthritis is crucial for early intervention and improving outcomes in affected children.