Each Sudoku is made of 81 cells, divided into 9 rows, 9 columns, and 9 boxes. The boxes are 3 cells by 3 cells, and are marked off by the thicker lines. Some of the cells contain a digit, 1 through 9. The object is to fill in the empty cells so that the digits 1 through 9 appear:      • exactly once in each row      • exactly once in each column      • exactly once in each 3 x 3 box Note: games require Adobe Flash Player. If game does not load, try installing the newest Flash Player. This game takes a few seconds to load.