Ten-pin bowling is a sport in which a "bowler" rolls a bowling ball down a wood-structure or synthetic (polyurethane) lane and towards ten pins positioned at the end of the lane. The objective is to score points by knocking down as many pins as possible. Three finger holes are drilled into a traditional bowling ball, and weights vary considerably to make the sport playable for all ages. The pins are arranged in a triangular position by an automated machine. While professional ten-pin bowling tournaments are held in numerous countries, the sport is commonly played as a hobby by millions of people around the world.