A tuning peg is a small mechanical device found on stringed instruments like guitars, violins, and cellos. It is used to adjust the tension of the strings, which in turn changes their pitch. By turning the tuning peg clockwise or counterclockwise, musicians can raise or lower the pitch of the string to achieve the desired sound. Tuning pegs are typically made of materials like metal or plastic and are designed to hold the strings securely in place. Properly functioning tuning pegs are essential for maintaining the instrument's tuning stability, allowing musicians to play in tune during performances and practice sessions.