Sudoku was originally called "Number Place". It became popular in Japan in the mid-80s, where it was re-named "sudoku", which translates to "the digits must be single".
In "Sudoku", start in tutorial mode if you're a beginner, or try Diabolic Mode if you're a seasoned player. You can also toggle the timer on and off for either a challenging or more zen experience.
“Sudoku”, complete with unlimited 6x6 boards and saves, drops in price today from £3.96 to £0.