History of Sudoku

Le Siècle, a French daily, produced a 9x9 grid with 3x3 sub-squares as early as 1892, but used double-digit numbers rather than the familiar 1-9. In 1895, another French daily, La France, created a puzzle that used the numbers 1-9 but did not mark the 3x3 sub-squares. These weekly puzzles were a feature of newspaper titles including L'Echo de Paris for about a decade but disappeared about the time of the First World War.

The modern Sudoku was designed anonymously by Howard Garns, a 74-year-old retired architect and freelance puzzle constructor, and first published in 1979. Garns added a third dimension to the traditional Roman practice of Latin Squares and presented the creation as a puzzle, providing a partially-completed grid and requiring the solver to fill in the rest. The puzzle was first published in New York by the specialist puzzle publisher Dell Magazines in its magazine Dell Pencil Puzzles and Word Games, under the title Number Place.

The puzzle was introduced in Japan by Nikoli in the paper Monthly Nikolist in April 1984 as Suuji wa dokushin ni kagiru, which can be translated as "the numbers must be single" or "the numbers must occur only once." The puzzle was named by Maki Kaji, the president of Nikoli. At a later date, the name was abbreviated to Sudoku, taking only the first kanji of compound words to form a shorter version. In 1986, Nikoli introduced two innovations: the number of givens restricted to no more than 32 and puzzles became "symmetrical" (meaning the givens were distributed in rotationally symmetric cells). It is now published in mainstream Japanese periodicals, such as the Asahi Shimbun.

Popularity in the media

In 1997, retired Hong Kong judge Wayne Gould, 59, a New Zealander, saw a partly completed puzzle in a Japanese bookshop. Over 6 years he developed a computer program to produce puzzles quickly. Knowing that British newspapers have a long history of publishing crosswords and other puzzles, he promoted Sudoku to The Times in Britain, which launched it on 12 November 2004 (calling it Su Doku). The immense surge in popularity of Sudoku in British newspapers and internationally has led to it being dubbed in the world media in 2005 the "fastest growing puzzle in the world" and the "Rubik's cube of the 21st century".

By April and May 2005 the puzzle had become popular in these publications and it was rapidly introduced to several other national British newspapers including The Independent, The Guardian, The Sun (where it was labelled Sun Doku), and The Daily Mirror. As the name Sudoku became well-known in Britain, the Daily Mail adopted it in place of its earlier name "Codenumber". Newspapers competed to promote their Sudoku puzzles, with The Times and the Daily Mail each claiming to have been the first to feature Sudoku.

The rapid rise of Sudoku from relative obscurity in Britain to a front-page feature in national newspapers attracted commentary in the media and parody (such as when The Guardian's G2 section advertised itself as the first newspaper supplement with a Sudoku grid on every page). Sudoku became particularly prominent in newspapers soon after the 2005 general election leading some commentators to suggest that it was filling the gaps previously occupied by election coverage. Recognizing the different psychological appeals of easy and difficult puzzles, The Times introduced both side by side on 20 June 2005. From July 2005, Channel 4 included a daily Sudoku game in their Teletext service. On 2 August, the BBC's programme guide Radio Times featured a weekly Super Sudoku.

The world's first live TV Sudoku show, Sudoku Live, was broadcast on 1 July 2005 on Sky One. It was presented by Carol Vorderman. Nine teams of nine players (with one celebrity in each team) representing geographical regions competed to solve a puzzle. Each player had a hand-held device for entering numbers corresponding to answers for four cells. The audience at home was in a separate interactive competition. A Sky One publicity stunt to promote the programme with the world's largest Sudoku puzzle went awry when the 275 foot (84 m) square puzzle was found to have 1,905 correct solutions. The puzzle was carved into a hillside in Chipping Sodbury, near Bristol, England, in view of the M4 motorway.

Dr. House was clearly seen working on a Web Sudoku puzzle on his office computer in one scene of the December 13 2005 episode of House, M. D.; Sudoku is now banned on the studio set due to the cast constantly playing it.

In the The Da Vinci Code parody from the 2006 MTV Movie Awards, Jessica Alba finds a body on the ground with a Sudoku puzzle on his stomach. Alba begins to take her pen out and tries to think quickly.

During February 7th's episode of The Daily Show, correspondent Jason Jones suggested that to ease the conflict over the Jyllands-Posten Muhammed caricatures, newspapers should be stripped down to only featuring Sudoku puzzles.

There are also Sudoku video games, such as Sudoku XP for PCs, Go! Sudoku for the PSP, "Dr. Sudoku" for the GBA and two sudoku games for the DS: Sudoku Mania and Sudoku Gridmaster. Sudoku puzzles are also featured in Brain Age and Big Brain Academy. In addition, various LCD handhelds exist, using either a number pad and directional keys or a touch screen.

Competitions

The first world championship was held in Lucca, Italy from 10 to 12 March 2006; it was won by Jana Tylová, a 31-year-old accountant from the Czech Republic. The competition included numerous variants.