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Why does a bowling ball spin?

The surface of the bowling lane is nearly frictionless, disallowing the ball to shift position based upon the acceleration due to friction.  There must therefore be another force driving the bowling ball to spin in a certain direction.  We will be observing the three different types of bowling balls, plastic, polyurethane, and reactive resin.

Plastic

The basic type of ball that the average person uses is plastic.  This is the type of ball that most alleys have on their racks because they are relatively easy to control, and relatively cheap to produce.  The ball has no mechanisms for spin, and even if the ball has circular motion, the ball will not move except in the direction of initial acceleration.  These balls are especially useful for beginners because it is easier to control and will not spin.

Polyurethane

These balls are more common in the higher level of bowling, as they allow a more advantageous angle for hitting the head pin.  This better angle is caused by a rotation in the ball that causes it to spin closer to the center of the lane from one side of the lane.  This rotation in the ball is caused by an internal mechanism for the ball trying to stabilize itself, and the ball will use this mechanism to move in a resulting straight line, however this straight path is at an angle that would not be able to be achieved if the ball followed only a straight line.

Reactive Resin

These balls will shift on the boards in a slightly different manner than with the polyurethane balls.  While it has a stabilizing core like the polyurethane ball, this one also contains a system of particles on the outer shell to help the ball pick up oil, and add friction to the lane, allowing for a grip on the boards, and therefore spin into an angle that is most advantageous to getting a strike.

Plastic

Polyurethane

Reactive Resin