Originally called simply Number Place, the first puzzle was created by Howard Garnes, a freelance puzzle constructor, in 1979. The puzzle was first published in New York in the late 1970s 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 “Suji wa dokushin ni kagiru “, which can be translated as “the numbers must be single” or “the numbers must occur only once” ( literally means “single; celibate; unmarried”). The puzzle was named by Kaji Maki , the president of Nikoli. At a later date, the name was abbreviated to Sudoku ;, pronounced sue-do-koo; ; = number, doku = single); it is a common practice in Japanese to take only the first kanji of compound words to form a shorter version. In 1986, Nikoli introduced two innovations which guaranteed the popularity of the puzzle: the number of givens was restricted to no more than 30 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. Within Japan, Nikoli still holds the trademark for the name Sudoku; other publications in Japan use alternative names.
In 1989, Loadstar/Softdisk Publishing published DigitHunt on the Commodore 64, which was apparently the first home computer version of Sudoku. At least one publisher still uses that title.
Yoshimitsu Kanai published his computerized puzzle generator under the name Single Number (the English translation of ‘sudoku’) for the Apple Macintosh in 1995 in Japanese and English, and in 1996 for the Palm (PDA).
Bringing the process full-circle, Dell Magazines, which publishes the original Number Place puzzle, now also publishes two Sudoku magazines: Original Sudoku and Extreme Sudoku. Additionally, Kappa reprints Nikoli Sudoku in GAMES Magazine under the name Squared Away; the New York Post, USA Today, and San Francisco Chronicle now also publish the puzzle. It is also often included in puzzle anthologies, such as The Giant 1001 Puzzle Book (under the title Nine Numbers).