What are mulligans in golf?

Mulligans are informal do-overs or second chances that allow a golfer to replay a shot without penalty. They are not recognized by the official rules of golf, but are often used in casual or friendly games to give players a break after a poor shot. The use and number of mulligans allowed are usually agreed upon by the group before play begins. In formal tournaments or competitions, mulligans are not permitted. The term is believed to have originated from early 20th-century golf culture.