Pool, covering numerous pocket billiards games generally played on six-pocket tables of 7-, 8-, 9-, or 10-foot length, including among others eight-ball (the world's most widely played cue sport), nine-ball (the dominant professional game), ten-ball, straight pool (the formerly dominant pro game), one-pocket, and bank pool.
Carom billiards, referring to games played on tables without pockets, typically 10 feet in length, including straight rail, balkline, one-cushion carom, three-cushion billiards, artistic billiards, and four-ball.
There are three major subdivisions of games within cue sports: In colloquial usage, the term billiards may be used to refer to games such as pool, snooker, or Russian pyramid. For example, in British and Australian English, billiards usually refers exclusively to the game of English billiards, while in American and Canadian English it is sometimes used to refer to a particular game or class of games, or to all cue games in general, depending upon dialect and context. While that familiar name is still employed by some as a generic label for all such games, the word's usage has splintered into more exclusive competing meanings in various parts of the world. Historically, the umbrella term was billiards.