Sudoku. You must remember these three rules to meet the moon. Sudoku is a puzzle game where you insert the numbers 1 to 9 into a grid of 9 rows and columns so that the numbers do not overlap within each row, column, and 3x3 square.

Sudoku. You must remember these three rules to meet the moon. Sudoku is a puzzle game where you insert the numbers 1 to 9 into a grid of 9 rows and columns so that the numbers do not overlap within each row, column, and 3x3 square.