Rules:

Sudoku, also known as Number Place, is a logic-based placement puzzle. The aim of the puzzle is to enter a numerical digit from 1 through 9 in each cell of a 9x9 grid made up of 3x3 subgrids (called "regions"), starting with various digits given in some cells (the "givens"); each row, column, and region must contain only one instance of each numeral. Completing the puzzle requires patience and logical ability.

For good advice on how to solve Sudoku puzzles, visit Wikipedia.org.