The Checkers reference article from the English Wikipedia on 24-Jul-2004
(provided by Fixed Reference: snapshots of Wikipedia from wikipedia.org)

Checkers

Videos from a children's charity on sponsorship

Checkers boardEnlarge

Checkers board

This article deals with the game of checkers. Checkers is also the name of a Cocker Spaniel after whom Richard Nixon's infamous Checkers speech was named. This article is also not to be confused with Chequers, the official country residence of the Prime Minister of the United Kingdom

Checkers (or draughts) is a group of board games which involve the "jumping" of enemy pieces.

Table of contents
1 History
2 Rules
3 Computer Players
4 Computational complexity
5 Variants
6 Famous Checkers Players
7 See also
8 External links

History

The game of draughts is thought to have originated in around 1100 AD, probably in southern France. It is thought the inventor created this board game by using a Chessboard, with the rules of Alquerque.

The pieces were originally called "ferses", the name that was given to chess queens at the time, and the draught ferses moved in the same way as the queen did in chess. Note however at this time, the queen was able only to move one square per turn. The one new move this game introduced was the ability to jump over opponent's pieces and take them. At this time the game was known as "Fierges".

In Philip Mouskat's "Chronique" (1243) is a reference to the use of "Kings" suggesting that the ability to promote a piece existed at this time.

When in Chess "ferses" were renamed to "Dame", the same occurred in Draughts, the games name also changed to "Dames". While it is thought that the original Fierges had a compulsory capture rule, there is no evidence that this rule existed in Dames. This rule was however reintroduced in France in the year 1535. Modern play includes this rule.

The name "Checkers" originated with European settlers in the United States.

Rules

English draughts (checkers) is played on an 8x8 chessboard, but only uses the dark squares.

right

The rules are:

In tournament checkers, a variation called three-move restriction is preferred. The first three moves are drawn at random from a set of accepted openings. Two games are played with the chosen opening, each player having a turn at either side. This tends to reduce the number of draws and can make for more exciting matches. Three-move restriction has been played in the United States championship since 1934. A two-move restriction was used from 1900 until 1934 in the United States and in the British Isles until the 1950s. Before 1900, championships were played without restriction: this style is called go-as-you-please.

Computer Players

The first computer player of checkers was written by Arthur Samuel, a researcher from IBM. Other than it being one of the most complicated game playing programs written at the time, it is also well known for being one of the first adaptive programs. It learned from its opponents and adjusted its strategy accordingly.

The strongest checkers player is a program called Chinook written by a team led by Jonathan Schaeffer. Marion Tinsley, world champion from 1955-1962 and 1975-1991, won a match against the machine in 1992. In 1994, he had to resign in the middle of an even match because of health reasons; he died shortly thereafter. Chinook was retired after winning the world man-machine champion title.

Today's PC programs are stronger than the best humans. The man-machine title is not as meaningful as it was 10-20 years ago, because most human experts are over 60 years old, as few young players have invested the effort to become experts.

Computational complexity

It is a common misconception that checkers has been solved. The best computers can now beat all humans, but checkers is not yet completely solved. It is generally expected that checkers will be solved by 2010.

The number of legal positions in checkers is estimated to be 1018, and it has a game-tree complexity of approximately 1031.

When checkers is generalized so that it can be played on an n-by-n board, the problem of determining if the first player has a win in a given position is EXPTIME-complete.

Variants

Famous Checkers Players

See also

External links