As per the Wikipedia:
A glider or platform rocker is a type of rocking chair that moves as a swing seat, where the entire frame consists of a seat attached to the base by means of a double-rocker four-bar linkage. The non-parallel suspension arms of the linkage cause the chair to simulate a rocking-chair motion as it swings back and forth.
From the above meaning it becomes quite clear that a Glider rocker chair comes with both rock and glide.
BENEFITS OF GLIDER: