Carpal Tunnel Syndrome is a condition where the median nerve passing through the carpal tunnel in the wrist becomes compressed, causing pain, numbness, and loss of function in the hand. It is caused by repetitive motions, vibration, force, poor ergonomics, or other factors that reduce the size of the carpal tunnel. Symptoms include pain, numbness, and weakness in the hand that is often worse at night. Treatment involves limiting aggravating activities, splinting, anti-inflammatory drugs, steroid injections, or surgery to relieve pressure on the median nerve.