Force of friction which comes into play, between two surfaces, while one is rolling over the other is called rolling friction.
Rolling friction is applicable for bodies whose point of contact keeps changing
It is the force that opposes the motion of a body which is rolling over the surface of another
Bowling balls, rotating wheels are examples illustrating Rolling friction
Rolling friction is similar to kinetic friction.
So, fr= µr N
Here µr is the coefficient of rolling friction and N is the normal force.
Coefficient of Rolling friction is lesser than that of Kinetic friction.
fr < fk < fs