The most common type of linear bearing is a rolling linear bearing, which has a minor frictional surface for linear motion. The rolling elements are balls or rollers housed between the mating grooves in the bearing and guide rails.
The linear guide's linear speed is related to the ball or roller diameter; as the ball diameter grows, so does the linear guide's linear speed. The linear bearing's loading capacity in a specific direction is affected by the contact angle, which is measured on the horizontal.