Also known as Number Place, Sudoku puzzles are actually logic-based placement puzzles. The object of the game is to enter a numerical digit from 1 through 9 in each cell that is found on a 9 x 9 grid which is sundivided into 3 x 3 subgrids or regions. Several digits are often given in some cells. These are referred as givens. Ideally, at the end of the game, every row, column, and region must contain only one instance of each numeral from 1 through 9. Patience and logic are two qualities needed in order to complete the game.
Number puzzles very much similar to the Sudoku Puzzles have already been in existence and have found publication in many newspapers for over a century now. For instance, Le Siecle, a daily newspaper based in France, featured, as early as 1892, a 9×9 grid with 3×3 sub-squares, but used only double-digit numbers instead of the current 1-9. Another French newspaper, La France, created a puzzle in 1895 that utilized the numbers 1-9 but had no 3×3 sub-squares, but the solution does carry 1-9 in each of the 3 x 3 areas where the sub-squares would be. These puzzles were regular features in several other newspapers, including L’Echo de Paris for about a decade, but it unfortunately disappeared with the advent of the first world war.
Howard Garns, a 74-year-old retired architect and freelance puzzle constructor, was considered the designer of the modern Sudoku Puzzles. His design was first published in 1979 in New York by Dell, through its magazine Dell Pencil Puzzles and Word Games under the heading Number Place. Garns’ creation was most likely inspired by the Latin square invention of Leonhard Euler, with a few modifications, basically, with the addition of a regional restriction and the presentation of the game as a puzzle, providing a partially-complete grid and requiring the solver to fill in the empty cells.
Sudoku Puzzles were then taken to Japan by the puzzle publishing company Nikoli. It introduced the game in its paper Monthly Nikoli sometime in April 1984. Nikoli president Maki Kaji gave it the name Sudoku, a name that the company holds trademark rights over; other Japanese publications which featured the puzzle have to settle for alternative names.
In 1989, Sudoku Puzzles entered the video games arena when it was published as DigitHunt on the Commodore 64. It was introduced by Loadstar/Softdisk Publishing. Since then, other computerized versions of the Sudoku Puzzles have been developed. For instance, Yoshimitsu Kanai made several computerized puzzle generator of the game under the name Single Number for the Apple Macintosh in 1995 both in English and in Japanese language; for the Palm (PDA) in 1996; and for Mac OS X in 2005.