Sudoku (数独 sūdoku?, すうどく) English pronunciation: /suːˈdoʊkuː/ soo-doh-koo is a logic-based, combinatorial number-placement puzzle. The objective is to fill a 9×9 grid with digits so that each column, each row, and each of the nine 3×3 sub-grids that compose the grid (also called "boxes", "blocks", "regions", or "sub-squares") contain all of the digits from 1 to 9. The puzzle setter provides a partially completed grid, which typically has a unique solution.

Questions about Sudoku include:

Validating a Sudoku:

Solving a Sudoku:

and more.