The object of Sudoku puzzles is to place the numerals 1 through 9 in a 9 x 9 grid so that each row, each column and each 3 x 3 grid contains each number one time only. Options available: 12000 puzzles with 4 difficulty levels, save incomplete puzzles, hints, check for incorrect, numbers or check entire puzzle, restart puzzle, solve puzzle, choice of background, number and highlight colors, eight puzzles in the trial version; 400 in the full version, free updates, complete help file, complete setup and uninstall.