A golf fade is a shot that curves from left to right for a right-handed golfer (and vice versa for a left-handed golfer). Fades can be useful for playing around obstacles, such as trees or bunkers, or for landing the ball on a specific part of the green.
To hit a fade, you need to swing the club with an outside-in path and close the clubface at impact. This will cause the ball to start out going straight, but then curve to the right (or left) as it flies. The amount of fade will depend on how much you close the clubface and how outside-in your swing path is.