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. Popular versions include eight-ball and nine-ball. An obsolete term for pool is six-pocket.
There are hundreds of pool games. Some of the more well known include eight-ball, nine-ball.
In the United States, the most commonly played game is eight-ball. The goal of eight-ball, which is played with a full rack of fifteen balls and the cue ball, is to claim a suit (commonly stripes or solids in the US, and reds or yellows in the UK), pocket all of them, then legally pocket the 8 ball, while denying one’s opponent opportunities to do the same with their suit, and without sinking the 8 ball early by accident. In the United Kingdom the game is commonly played in pubs, and it is competitively played in leagues on both sides of the Atlantic. The most prestigious tournaments including the World Open are sponsored and sanctioned by the International Pool Tour. Rules vary widely from place to place (and between continents to such an extent that British-style eight-ball pool/blackball is properly regarded as a separate game in its own right). Pool halls in North America are increasingly settling upon the World Pool-Billiard Association International Standardised Rules. But tavern eight-ball (also known as “bar pool”), typically played on smaller, coin-operated tables and in a “winner keeps the table” manner, can differ significantly even between two venues in the same city. The growth of local, regional and national amateur leagues may alleviate this confusion eventually.
One of many correct nine ball racks: the 1 ball at the apex centered over the foot spot, the 9 ball at center, the other balls placed randomly, and all balls touching.
Nine-ball uses only the 1 through 9 balls and cue ball. It is a rotation game: The player at the table must make legal contact with the lowest numbered ball on the table or a foul is called. The game is won by legally pocketing the nine ball. Nine-ball is the predominant professional game, though as of 2006–2008 there have been some suggestions that this may change, in favor of ten-ball.[clarification needed] There are many local and regional tours and tournaments that are contested with nine-ball. The World Pool-Billiard Association (WPA) and its American affiliate, the Billiard Congress of America (BCA), publish the World Standardized Rules. The European professional circuit has instituted rules changes to make it more difficult to achieve a legal break shot.
The largest nine-ball tournaments are the independent U.S. Open Nine-ball Championship and the WPA World Nine-ball Championship for men and women. Male professionals have a rather fragmented schedule of professional nine-ball tournaments. The United States Professional Pool Players Association (UPA) has been the most dominant association of the 1990s and 2000s. A hotly contested event is the annual Mosconi Cup, which pits invitational European and U.S. teams against each other in one-on-one and scotch doubles nine-ball matches over a period of several days. The Mosconi Cup games are played under the more stringent European rules, as of 2007.