You can play an assortment of games on your billiards table with different balls and rules. The colour and diameter change most often, though some games call for different weights. The hardness (density) and polish (friction) affect playability, too. These properties can alter accuracy, reflectivity, and rolling distance.
The material of the ball also impacts gameplay. Most commonly, billiards balls are made of phenolic resin or a similar plastic. That said, some sets are made from wood, clay, and ivory.
American 8-Ball Pool Set
Balls in this set measure 2 ¼ inches in diameter. They come in two numbered suits—solids and stripes. There are 15 object balls in total (cue ball excluded). The weight of each ball depends on its material, though the standard range is between 5 ½ and 6 ounces.
Snooker Ball Set
Snooker involves one cue ball, 15 red balls, and 6 object balls. The object balls include the following colours: yellow, green, brown, blue, pink, and black. Each ball is approximately 2 1⁄8 inches in diameter.
Carom Billiards Balls
Carom billiards sets come with the fewest balls. In fact, carom tables do not even have pockets! There are three balls in total: one yellow, one red, and one white. Each is 2 7/16 inches in diameter.
This English variant comes with seven yellow and seven red balls, each 2 1/8 inches in diameter. Balls in this set are unnumbered besides the 8-ball (the black ball).
Many manufacturers sell balls not intended for real gameplay. These come in different sizes, colours, and weights, depending on their purpose. For example, some cue balls have rings as targets for new players. Different rings produce unique shots like the backspin or “English”.