backgammon n : a board game for two players; pieces move according to throws of the dice
- , /ˈbæk.gæm.ən/
- A board game for two players in which each has 15 stones which move between 24 triangular points according to the roll of a pair of dice; the object is to move all of one's pieces around, and bear them off the board.
- In the context of "backgammon": A victory in the game when the loser has not borne off a stone, and still has one or more stones in the winner's inner home row or on the bar.
- Alsatian: backgammon
- Arabic: (ʈāwilä)
- Asturian: backgammon
- Bosnian: tavla , triktrak
- Bulgarian: табла (tabla)
- Catalan: backgammon
- Czech: vrhcáby m|p
- Danish: backgammon
- Dutch: backgammon
- Finnish: backgammon
- French: backgammon
- German: backgammon
- Greek: τάβλι (tavla) (el)
- Hebrew: שש בש (shash d?ash)
- Italian: backgammon
- Modern/Primary Romanization: bākugammon
- Hepburn Romanization: baakugammon
- Modern/Primary Romanization: bākugammon
- Korean: 주사위 놀이 (jusawi nori)
- Latin: nerdiludium
- Luxemburgian: backgammon
- Macedonian: табла (tabla)
- Norwegian: backgammon
- Persian: (nard)
- Polish: tryktrak m|f
- Portuguese: gamão
- Russian: нарды (nard'i)
- Slovene: backgammon
- Spanish: backgammon
- Swedish: backgammon
- Turkish: tavla
- Urdu: (nard)
victory in the game
- To win at a backgammon game with the opponent having one or more pieces in the winner's inner home row or on the bar.
to win by a backgammon
Backgammon is a board game for two players in which the playing pieces are moved according to the roll of dice. A player wins by removing all of his checkers from the board. There are many variants of backgammon, most of which share common traits. Backgammon is a member of the tables family, one of the oldest classes of board games in the world.
Although luck plays an important role, there is a large scope for strategy. With each roll of the dice a player must choose from numerous options for moving his checkers and anticipate possible counter-moves by the opponent. Players may raise the stakes during the game. There is an established repertory of common tactics and occurrences.
Like chess, backgammon has been studied with great interest by computer scientists. Owing to this research, backgammon software has been developed capable of beating world-class human players.
The ancient Egyptian game senet resembled backgammon, with moves controlled by the roll of dice. However, the Royal Game of Ur, played in ancient Mesopotamia, is a more likely ancestor of modern day tables games. Excavations at the "Burnt City" in Iran have shown that a similar game existed there around 3000 BC. The artifacts include two dice and 60 checkers, and the set is believed to be 100 to 200 years older than the sets found in Ur.
The ancient Romans played a number of games remarkably similar to backgammon. Ludus duodecim scriptorum ("Game of twelve lines") used a board with three rows of 12 points each, and the checkers were moved across all three rows according to the roll of dice. Little specific text about the gameplay has survived. Tabula, meaning "table" or "board", was a game mentioned in an epigram of Byzantine Emperor Zeno (AD 476–481). It was similar to modern backgammon in that the object of the game was to be the first to bear off all of one's checkers. Players threw three dice and moved their checkers in opposing directions on a board of 24 points.
In the 11th century Shahnameh, the Persian poet Ferdowsi credits Burzoe with the invention of the tables game nard in the 6th century. He describes an encounter between Burzoe and a Raja visiting from India. The Raja introduces the game of chess, and Burzoe demonstrates nard, played with dice made from ivory and teak. (Today, Nard is the name for the Persian version of backgammon, which has different initial positions and objectives.)
The jeux de tables, predecessors of modern backgammon, first appeared in France during the 11th century and became a favorite pastime of gamblers. In 1254, Louis IX issued a decree prohibiting his court officials and subjects from playing. Tables games were played in Germany in the 12th century, and had reached Iceland by the 13th century. The Alfonso X manuscript Libro de los juegos, completed in 1283, describes rules for a number of dice and tables games in addition to its extensive discussion of chess. By the 17th century, tables games had spread to Sweden. A wooden board and checkers were recovered from the wreck of the Vasa among the belongings of the ship's officers. Backgammon appears widely in paintings of this period, mainly those of Dutch and German painters (Van Ostade, Jan Steen, Bosch and others). One surviving artwork is "Cardsharps" by Caravaggio (The backgammon board is in the lower left.) Others are the Hell of Bosch and interior of an Inn by Jan Steen.
In the 16th century, Elizabethan laws and church regulations prohibited playing tables, but by the 18th century backgammon was popular among the English clergy.
In English, the word "backgammon" is most likely derived from "back" and Middle English "gamen", meaning "game" or "play". The earliest use documented by the Oxford English Dictionary was in 1650.
The most recent major development in backgammon was the addition of the doubling cube. It was first introduced in the 1920s in New York City among members of gaming clubs in the Lower East Side. The cube required players not only to select the best move in a given position, but also to estimate the probability of winning from that position, transforming backgammon into the expected value-driven game played in the 20th and 21st centuries.
Points 1 through 6 are called the home board or inner board, and points 7 through 12 are called the outer board. The 7-point is referred to as the bar point, and the 13-point as the mid point.
MovementTo start the game, each player rolls one die, and the player with the higher number moves first using both the numbers shown. Both dice must land completely flat on the right hand side of the gameboard. The players then alternate turns, rolling two dice at the beginning of each turn.
Some money games use the "automatic double" rule. If both opponents roll the same opening number, the doubling cube is incremented on each occasion yet remains in the middle of the board, available to either player. When a player decides to double his opponent, the value is then a double of whatever face value is shown (e.g. if two automatic doubles have occurred putting the cube up to 4, the first in-game double will be for 8 points).
A variant of the doubling cube "beaver" is the "raccoon." The player who doubled his opponent, seeing him beaver the cube, may in turn then double the stakes once again ("raccoon") as part of that cube phase before any dice are rolled. His opponent retains the doubling cube. E.g. White doubles Black to 2 points, Black accepts then beavers the cube to 4 points; White, confident of a win, raccoons the cube to 8 points, whilst Black retains the cube. Such a move adds greatly to the risk of having to face the doubling cube coming back at 8 times its original value when first doubling the opponent (offered at 2 points, counter offered at 16 points) should the luck of the dice change.
The Jacoby rule allows gammons and backgammons to count for their respective double and triple values only if the cube has already been offered and accepted. This encourages a player with a large lead to double, possibly ending the game, rather than to play it to conclusion hoping for a gammon or backgammon. The Jacoby rule is widely used in money play but is not used in match play.
The Crawford rule is designed to make match play more equitable for the player in the lead. If a player is one point away from winning a match, that player's opponent will always want to double as early as possible in order to catch up. Whether the game is worth one point or two, the trailing player must win to continue the match. To balance the situation, the Crawford rule requires that when a player first reaches a score one point short of winning, neither player may use the doubling cube for the following game, called the Crawford game. After the Crawford game, normal use of the doubling cube resumes. The Crawford rule is used in tournament match play. The popular GNU Backgammon software has an option for this, which is described as the 'Egyptian Rule', however the origin of that name might be due to a humorous invention.
Acey-deucey is a variant of backgammon in which players start with no checkers on the board, and must bear them on at the beginning of the game. The roll of 1-2 is given special consideration, allowing the player, after moving the 1 and the 2, to select any doubles move of his choice. A player also receives an extra turn after a roll of 1-2 or of doubles.
Hypergammon is a variant of backgammon in which players have only three checkers on the board, starting with one each on the 24-, 23- and 22-points. The game has been strongly solved, meaning that exact equities are available for all 32 million possible positions.
Nackgammon is a variant of backgammon invented by Nack Ballard in which players start with one fewer checker on the six point and midpoint and two checkers on the 23 point.
Prison is a variant of backgammon in which players start with all 15 checkers on the 24 point and when a solo checker gets hit, instead of being taken off the board, the opponent's checker remains on top of it, imprisoning that piece until the opponent moves the last checker off that piece and if a player gets hit on the 24 piece, that player automatically loses two games.
Strategy and tactics
Backgammon has an established opening theory, although it is less detailed than that of games like chess. The tree of positions expands rapidly because of the number of possible dice rolls and the moves available on each turn. Recent computer analysis has offered more insight on opening plays, but the midgame is reached quickly. After the opening, backgammon players frequently rely on some established general strategies, combining and switching among them to adapt to the changing conditions of a game.
The most direct strategy is simply to avoid being hit, trapped, or held in a stand-off. A "running game" describes a strategy of moving as quickly as possible around the board, and is most successful when a player is already ahead in the race. When this fails, one may opt for a "holding game", maintaining control of a point on one's opponent's side of the board, called an anchor. As the game progresses, this player may gain an advantage by hitting an opponent's blot from the anchor, or by rolling large doubles that allow the checkers to escape into a running game. A few clubs offer additional services, maintaining their own facilities or offering computer analysis of troublesome plays. Some club leaders have noticed a recent growth of interest in backgammon, and attribute it to the game's popularity on the internet.
A backgammon chouette permits three or more players to participate in a single game, often for money. One player competes against a team of all the other participants, and positions rotate after each game. Chouette play often permits the use of multiple doubling cubes. The top players at regional tournaments often compete in major national and international championships. Winners at major tournaments may receive prizes of tens of thousands of dollars.
International competitionPrior to 1979, there was no single world championship competition in backgammon, although a number of major tournaments were held in Las Vegas, Nevada and the Bahamas. Since 1979, the World Backgammon Championship in Monte Carlo has been widely acknowledged as the top international tournament. The Monte Carlo tournament draws thousands of players and spectators, and is played over the course of a week.
GamblingWhen backgammon is played for money, the most common arrangement is to assign a monetary value to each point, and to play to a certain score, or until either player chooses to stop. The stakes are raised by gammons, backgammons, and use of the doubling cube. Backgammon is sometimes available in casinos. As with most gambling games, successful play requires a combination of luck and skill, as a single dice roll can sometimes significantly change the outcome of the game.
In the late 1980s, backgammon programmers found more success with an approach based on artificial neural networks. TD-Gammon, developed by Gerald Tesauro of IBM, was the first of these programs to play near the expert level. Its neural network was trained using temporal difference learning applied to data generated from self-play. According to assessments by Bill Robertie and Kit Woolsey, TD-Gammon's play was at or above the level of the top human players in the world. and Snowie as well as the shareware BGBlitz and the free software GNU Backgammon. These programs not only play the game, but offer tools for analyzing games and offering detailed comparisons of individual moves. The strength of these programs lies in their neural networks' weights tables, which are the result of months of training. Without them, these programs play no better than a human novice. For the bearoff phase, backgammon software usually relies on a database containing precomputed equities for all possible bearoff positions.
Internet playBackgammon software has been developed not only to play and analyze games, but also to facilitate play between humans over the internet. Dice rolls are provided by random or pseudorandom number generators. Real-time online play began with the First Internet Backgammon Server in 1992. It is the longest running non-commercial backgammon server and retains an international community of backgammon players. Yahoo Games offers a Java-based online backgammon room, and MSN Games offers a game based on ActiveX. Online gambling providers began to expand their offerings to include backgammon in 2006.
backgammon in Arabic: طاولة
backgammon in Bosnian: Backgammon
backgammon in Bulgarian: Табла
backgammon in Catalan: Backgammon
backgammon in Czech: Vrhcáby
backgammon in Danish: Backgammon
backgammon in German: Backgammon
backgammon in Modern Greek (1453-): Τάβλι
backgammon in Spanish: Backgammon
backgammon in Esperanto: Triktrako
backgammon in Basque: Backgammon
backgammon in Persian: تخته نرد
backgammon in French: Backgammon
backgammon in Galician: Backgammon
backgammon in Croatian: Backgammon
backgammon in Indonesian: Backgammon
backgammon in Interlingua (International Auxiliary Language Association): Backgammon
backgammon in Icelandic: Kotra
backgammon in Italian: Backgammon
backgammon in Hebrew: שש בש
backgammon in Georgian: ნარდი
backgammon in Latin: Nerdiludium
backgammon in Lithuanian: Nardai
backgammon in Limburgan: Triktraksjpèl
backgammon in Malay (macrolanguage): Backgammon
backgammon in Dutch: Backgammon
backgammon in Japanese: バックギャモン
backgammon in Norwegian: Backgammon
backgammon in Norwegian Nynorsk: Trikktrakk
backgammon in Polish: Tryktrak
backgammon in Portuguese: Gamão
backgammon in Russian: Нарды
backgammon in Sicilian: Backgammon
backgammon in Simple English: Backgammon
backgammon in Slovak: Backgammon
backgammon in Slovenian: Backgammon
backgammon in Serbian: Tavla
backgammon in Serbo-Croatian: Backgammon
backgammon in Finnish: Backgammon
backgammon in Swedish: Backgammon
backgammon in Turkish: Tavla
backgammon in Ukrainian: Нарди
backgammon in Vlaams: Backgammon
backgammon in Chinese: 雙陸棋