If you've been asked to move one ton, smoothly polished block which is placed on ground (another surface) from one place to another location. During initial attempt to move the block, the two surfaces in contact (the base of the block and the ground) resist movement. This is called Static friction. If we applied some more force, which is enough so that the surface begin to slide against one another. Once in motion, the resisting force is from kinetic or slippery friction, instead of static friction.
If beneath of that very same block we placed equally spaced rollers, the force which is required to move the block is considerably reduced. Do you know why? The rollers, in contact with the surfaces of ground and block, still encounter friction, but the rotating action of the rollers carries the block and have eliminated the resisting force of Kinetic friction; the friction encountered is now classified as Rolling friction. Rolling element bearings are designed based on this principle. They eliminate sliding friction and utilize the efficiency of rolling friction to carry load.