Where this idea comes from· Sudopedia
The names of the sudoku moves
The words in the Technique Book (single, hidden single, naked pair, pointing pair, box and line) were not handed down by a publisher. After sudoku spread in 2004 and 2005, solvers and people writing solving programs swapped methods on online forums, among them the Sudoku Programmers forum and the Sudoku Players’ Forum, and the names grew there.
One thing to hold: A solving program’s list of moves. Angus Johnson’s Simple Sudoku named its steps, and its set of moves became a yardstick other solvers used.
Why it matters: A move is easier to use once it has a name you can say, and these names were made by ordinary solvers sharing what worked.
What we don’t know: Nobody has shown who first used each name, and one idea often has several: a hidden single is also called a pinned digit, and pointing and claiming are also called locked candidates or box-line reduction.
Where this game comes from
Sudoku
Howard Garns, a retired architect from Indiana, is believed to have made the puzzle; Dell Magazines printed it in 1979 as “Number Place”. In 1984 the Japanese publisher Nikoli printed it and named it “the digits must be single”, shortened to sudoku. On 12 November 2004 The Times in London began printing it, brought there by Wayne Gould from New Zealand.
One thing to hold: A grid, a pencil and an eraser.
Why it matters: No arithmetic is needed — the digits are only names. Every step is a reason you can say out loud.
What we don’t know: Garns was named as the maker years later, from Dell’s lists of contributors; he died in 1989, before the puzzle became famous. French newspapers printed number-placing puzzles in the 1890s, but without the box rule.
Dates:
- 1979 Dell prints “Number Place”.
- 1984 Nikoli prints it in Japan and names it sudoku.
- 2004 The Times begins printing it in London.