Pocket billiards

Pool, also more formally known as pocket billiards (mostly in North America) or pool billiards (mostly in Europe and Australia), is the family of cue sports and games played on a pool table having six receptacles called pockets along the rails, into which balls are deposited as the main goal of play. An obsolete term for pool is six-pocket.

There are hundreds of pool games. Some of the more well known include eight-ball (and the variant blackball), nine-ball (with variants ten-ball and seven-ball), straight pool (14.1 continuous), one-pocket, and bank pool.

There are also hybrid games combining aspects of both pool and carom billiards, such as American four-ball billiards, cowboy pool, and bottle pool.

The Oxford English Dictionary states that pool is generally "any of various types of billiards for two or more players" but goes on to note that the first specific meaning of "a game in which each player uses a cue ball of a distinctive colour to pocket the balls of the other player(s) in a certain order, the winner taking all the stakes submitted at the start of the contest" is now obsolete, and its other specific definitions are all for games that originate in the United States.

In the United States, although the original "pool" game was played on a pocketless carom billiards table, the term later stuck to all new games of pocket billiards as the sport gained in popularity, and so outside the cue sports industry, which has long favored the more formal term pocket billiards, the common name for the sport has remained pool. The OxfordDictionaries.com definition no longer even provides the obsolete meaning found in the print edition, and refers only to the typical game "using two sets [each] of seven coloured and numbered balls ... with one black ball and a white cue ball" on a table with pockets.

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