Sudoku is a logic puzzle game in which the goal is to fill a grid with numbers so that each number only appears once in each row, column, and box (called a square) in the grid. It is the most popular logic puzzle in the world and has been played for thousands of years.

The difficulty of the puzzles increases as you go up in the game, and there are five levels of difficulty, ranging from easy to very difficult. There are several ways to play and earn achievements in Sudoku. You can also compete with your friends in the game by using the leaderboard and different achievements.