About Sudoku
Sudoku is a logic-based, combinatorial number-placement puzzle.
Number puzzles appeared in newspapers in the late 19th century, when French puzzle setters began
experimenting with removing numbers from magic squares. Le Siècle, a Paris daily, published a
partially completed 9x9 magic square with 3x3 subsquares on November 19, 1892. It was not a
Sudoku because it contained double-digit numbers and required arithmetic rather than logic to solve,
but it shared key characteristics: each row, column and subsquare added up to the same number.
How to play
In classic Sudoku, the objective is to fill a 9 x 9 grid with digits so that each column, each row,
and each of the nine 3 x 3 subgrids that compose the grid (also called "boxes", "blocks", or
"regions") contain all of the digits from 1 to 9. The puzzle setter provides a partially completed
grid, which for a well-posed puzzle has a single solution.
About this project
This project is open source.
Open source is source code that is made freely available for possible modification and
redistribution. Products include permission to use the source code, design documents, or
content of the product. The open-source model is a decentralized software development model that
encourages open collaboration.
Open source promotes universal access via an open-source or free license to a product's design or
blueprint, and universal redistribution of that design or blueprint. Before the phrase open
source became widely adopted, developers and producers have used a variety of other terms. Open
source gained hold with the rise of the Internet. The open-source software movement arose to
clarify copyright, licensing, domain, and consumer issues.