Friction is the force resisting the relative motion of solid surfaces, fluid layers and elements sliding against each other. Icy surfaces have very little; this is why if you were to apply a force to an object it would keep going (if there weren't any bodies to stop it). Newton's first law states that objects at rest will stay at rest and ones in motion will stay in motion, unless acted upon by an unbalanced force. Thus, on an icy surface an object may not stop. Lubrication is a process that is responsible for wearing at a surface, i.e. lowering an objects friction.