Osteoarthritis is a common joint disorder caused by cartilage breakdown from aging and joint stress. Symptoms include joint pain, swelling, cracking sounds, and limited range of motion. Risk factors include obesity, age, joint injuries, genetics, and certain jobs. Treatment focuses on exercises, weight control, rest, joint protection, pain management techniques, and sometimes drugs. Left untreated, osteoarthritis can lead to disability. Proper management helps slow the progression of symptoms.