The forehand and backhand are ways to swing the racket. The name indicates whether it is your palm or backhand that leads the swing, e.g. if you hold the racket in your right hand, swinging right-to-left is the forehand, and left-to-right is the backhand swing.
The forehand swing is believed to be more loose and rotational, while the backhand can be used with two hands to swing the racket more like a baseball bat, with all the accompanying velocity.