60 Fun Facts About Backgammon

How many pieces does each player start with in standard backgammon?

The pieces were traditionally called men, short for tablemen, and are increasingly called checkers in the United States.

How many points, the triangular spaces, does a backgammon board have in total?

Each side of the board carries a track of 12 isosceles triangles, forming a horseshoe-shaped path.

What is the term for removing your pieces from the board at the end of the game?

You may only start doing it once all fifteen of your pieces are in your home board.

A single opposing piece sitting alone on a point is called what?

Landing on it sends it to the bar, from where it must re-enter through your home board.

Where is a piece placed after it has been hit?

Early backgammon simply lifted hit men off the table; boards with a working bar came in by around 1850.

What is a triple-value win called?

It occurs when the loser has borne off nothing and still has a piece on the bar or in the winner's home board, and it gave the game its name.

How many points is a gammon worth?

A gammon happens when the winner bears off all fifteen pieces before the opponent has borne off any.

What happens when a player rolls doubles?

A roll of 5-5 therefore lets a player make four separate moves of five spaces each.

Which numbers are inscribed on the six faces of a doubling cube?

There is no upper limit on redoubles, so stakes can in theory rise to 128 or 256 even though the cube stops at 64.

At the start of a game the doubling cube sits between the players showing which number face up?

In that state the cube is said to be centred on 1, and either player may propose the first double.

What are points 1 through 6 on your own side called?

Points 7 to 12 are the outer board, and the 7-point is nicknamed the bar point.

Which point is sometimes nicknamed the "golden point"?

The 13-point is the midpoint and the 7-point is the bar point.

In the standard starting position, how many pieces begin on the 24-point, the farthest from home?

Three sit on the 8-point and five each on the 13-point and 6-point.

If only one of your two dice can be played, which must you use?

On any roll a player must use both numbers if it is at all possible to do so.

What must happen before a turn is officially over, allowing no more take-backs?

Until that moment a move can be undone and replayed an unlimited number of times.

In money play, what is an immediate redouble after accepting a double called?

The original doubler may refuse it and resign, or play on with the cube at four times its initial value.

What is the name for the counter-redouble a player may make after being beavered?

Accepting it means playing with the cube at eight times its initial value.

Which money-play rule says gammons and backgammons only count extra if the cube has already been turned?

It encourages a player with a big lead to double and end the game rather than play on hoping for a gammon.

Which backgammon rule bars the doubling cube for one game once a player is one point from winning the match?

It is named after John R. Crawford and is routine in match play, though such a game may never actually occur in a match.

What is a chouette?

Positions rotate after each game, and chouette play often permits several doubling cubes at once.

What is a "prime" in backgammon strategy?

A piece trapped behind six consecutive blocked points cannot escape until the wall breaks.

What does the pip count measure?

The difference between the two players' counts is a measure of the leader's racing advantage.

Under the simple "dead cube" model, what minimum winning chance justifies taking a double?

The live cube model, which credits the taker for owning the cube, puts the take-point at about 20% instead.

In which decade and where was the doubling cube first introduced?

Doubles had previously been recorded by placing common parlour matches on the bar.

The earliest known mention of backgammon by name comes from a letter written in which year?

James Howell spelled it Baggammon; the word most likely comes from back plus the Middle English gamen, meaning game.

Backgammon's immediate 16th-century predecessor was a tables game with which name?

It had been popular at the Scottish court of James IV and was considered the more serious game.

Who published A Short Treatise on the Game of Back-Gammon in 1753?

It was bound together with a similar text on whist.

The earliest identifiable tables game, Tabula, is described in an epigram of which Byzantine emperor?

Tabula had no bar, and all counters began off the board.

How many dice were used in the Byzantine game Tabula?

Modern backgammon kept Tabula's rules for hitting and for removing pieces at the end.

The Roman ancestor of tables games, ludus duodecim scriptorum, is first mentioned in which work?

The name means Game of twelve lines; its board had three rows of 12 points, and the Romans also called it alea.

Which French king's 1254 decree forbade his officials and subjects from playing tables games?

Tables games had arrived in France in the 11th century and become a favourite of gamblers.

A tables board and counters were recovered from the wreck of which famous 17th-century warship?

They were found among the belongings of the ship's officers.

The Persian game of Nard is linked by legend to which founder of the Sasanian dynasty?

The name nard is a shortening of nardashir, meaning brave Ardashir.

The Royal Game of Ur, an ancestor of tables games, is named after excavations by which archaeologist?

He dug the Royal Cemetery at Ur between 1922 and 1934.

Which British Museum curator reconstructed the rules of the Royal Game of Ur from a Babylonian tablet?

The tablet, written by the scribe Itti-Marduk-balatu, describes the game as played in the second century BC.

Which Russian-American aristocrat is dubbed the "Father of Modern Backgammon"?

He devised a tournament system in 1963 and organized the first major international tournament in March 1964.

In which city was the first backgammon world championship held in 1967?

The event stayed in Las Vegas until 1975 before moving to the Bahamas.

Who was the first backgammon world champion?

There was no championship at all in 1969 or 1970.

Since 1979 the World Backgammon Championship has been held in which location?

Promoter Lewis Deyong suggested merging the Bahamas and European events into one championship there.

Paul Magriel, author of what many call the bible of backgammon, was known by which nickname?

It came from a 64-board tournament he simulated against himself, in which the player designated X-22 eventually won.

Paul Magriel wrote a weekly backgammon column for which newspaper from 1977 to 1980?

He won the world championship in 1978, in the middle of that run.

A 1982 court case that ruled backgammon a game of skill rather than chance was heard in which US state?

Judge Stephen S. Walker acquitted tournament director Ted Barr of promoting gambling.

Gerald Tesauro developed TD-Gammon, the 1990s neural-network backgammon program, at which company?

Its name refers to temporal-difference learning, and it is often cited as an early success of reinforcement learning.

Roughly how many games of self-play trained TD-Gammon version 2.1 in 1993?

It reached a level just slightly below the top human players of the time.

In Hypergammon each player starts with one piece on each of which points?

Hugh Sconyers solved the game by computer around 1994, giving exact equities for all 32 million positions.

The tables game acey-deucey has been a favourite of which US service since World War I?

A man kept off the board for defensive purposes is traditionally called Oscar.

Plakoto, Fevga and Portes are three tables games played in sequence in Greece under which name?

The Turkish variation is called Tavla, while Gul bara and Tapa are popular in south-eastern Europe.

The Eastern Mediterranean name Shesh Besh combines words for six and five from which two languages?

Players across the region still announce their dice rolls in a mixture of Persian and Turkish numbers.

Which Syrian city became famous from the early 19th century for its wooden marquetry backgammon sets?

Syria's director of antiquities once said the game became the rage of the Ottoman Empire and stayed behind when the Turks left.

How did trictrac, the French tables pastime, fundamentally differ from backgammon?

Its 8th points were nicknamed the Devil's points because they were statistically the hardest to reach.

By the third roll of a backgammon game, roughly how many different positions are possible?

That explosion is why backgammon opening theory is far less developed than chess opening theory.

Which free-software backgammon engine, released in 2001, is part of the GNU project?

eXtreme Gammon, released in 2009, has been called the best backgammon player in the world.

Among casual players in which country is a maximum of five men per point a common house rule?

In the Middle East a common local variation instead disallows hit-and-run inside the inner table.

What bars the doubling cube for one game once a player is one point short of winning a match?

Named after John R. Crawford, it protects the leader; a Crawford game may never actually occur in a given match.

Which Hans Berliner program was the first computer to beat a reigning world champion at a board game?

It beat Luigi Villa 7-1, though Berliner admitted the dice had favoured the machine.

What is the strategy of holding anchors in the opponent's home board while far behind in the race?

The anchors block the opponent's pieces and set up chances to hit them as they come home.

The English word 'backgammon' most likely combines 'back' with which Middle English word?

The word first appears by name in a 1647 letter; the game's 16th-century predecessor was simply called Irish.

Which neural-net program released in 1998 could analyse an entire match rather than single positions?

It was written by André Nicoulin and Olivier Egger; eXtreme Gammon followed in 2009 with mobile versions.

In money play, what limit do players usually agree on for automatic doubles?

An automatic double turns the cube when both players roll the same number on the opening throw.

Which Japanese game is described as a close relative of backgammon?

Coan ki is an ancient Chinese tables game, while Persia's nard may be a direct ancestor.