Originally called Number Place. The Sudoku puzzle game was discovered during the late 19th century by some French nationals who were experimenting on a new puzzle to be published in their daily paper. However, the previous version was not based on logic but in arithmetic. By adding the numbers contained in the three by three sub-square, a specific number will be the result, and it should be the same with the other three by three sub-squares within the whole nine by nine grids. However, during 1895, a rival paper in France has made some alteration in the puzzle which will resemble the Sudoku puzzle that we have now.

Throughout the years, the Sudoku puzzle has post a great challenge in the readers if the French papers, which resulted into the rise of the popularity of the game. Because of such demand for the game, some publishers have made some bold steps and spearheaded the production of Sudoku puzzle magazines, which featured more Sudoku puzzles rather than articles and news. Later, the Sudoku magazine became a book which contained only Sudoku puzzles. Some of these books have some strategies and techniques included in them but generally contained unsolved Sudoku puzzles.

**The different types of Sudoku**

Basically, the Sudoku that we enjoy now is the most difficult of all its variations. These variations are defined by regions of cells or blocks. What we have now is the most common version which features a nine by nine grids with a three by three regions. Other versions featured different grid and regions; we have the four by four grids with two by two regions, the five by five grids with a pentonimo region or five equal squares. However, the variation is not only limited to the changes of the regions’ pattern or grids. It also includes the changing of the numbers into alphabets. It is called the alphabet Sudoku. It applies the same principle but uses letters or the alphabet instead of numbers. However, as the years went on, the popularity of the rest of the variations of the game had diminished, which lead to their non existence, leaving the regular Sudoku puzzle to remain.