Sudoku is a popular casual number game with simple rules but endless fun. Many educators consider it a great way to exercise the brain. It originated in Switzerland in the 18th century and has since become popular and developed in places like the United States and Japan.
The Sudoku board consists of 9 3×3 squares, each of which is further subdivided. The game requires players to fill in the numbers 1-9 in each small square, while ensuring that the numbers in each row, column, and each 3×3 small square of the entire large square are not repeated. The logic of Sudoku is clear and easy to understand, but the number combinations are ever-changing, full of challenges and surprises.