Each bowling pin is assigned a number so it can easily be identified. The first pin, or headpin, is Pin Number 1. All the other pins behind the head pin are numbered consecutively from Pin Number 2 to Pin Number 10. The bowling pins setup follows an equilateral triangle formation. The space between the pins that are next to each other is 12 inches.

Since there are ten pins set each time the pinsetter recycles a frame of bowling, the pins are, therefore, best referred to by an identifying number. The pin nearest you when all ten pins are standing is commonly referred to as the "Head Pin" and is also known as the "No. 1 pin".