The History of the Japanes puzzle game Sudoku

Sudoku initially became popular in Japan in 1986 and attained popularity throughout the world in 2004/5.

Sudoku, sometimes spelled Su Doku, is a placement puzzle, also known or Number Place in some parts of the world.

The aim of the puzzle is to enter a numeral from 1 through to 9 in each cell of a grid, most frequently a 9×9 grid made up of 3×3 subgrids (called "regions"), starting with various numerals given in some cells (the "givens").

A Sudoku puzzle has one unique solution and the difficulty varies depending on how many numbers you are given at the start, so the more numbers usually the easier the puzzle.

Just looking at the Sudoku starting grid, you should be able to deduce the number that must go in every square of the grid, number by number. You shouldn't have to guess at any values if the grid has been correctly generated using the proper rules.

The great thing about Sudoku is it is very simple to lean, requires no calculations, and provides a surprisingly wide variety of logic situations.

All that's requires are your brain and some quiet concentration. It's no wonder they have become amongst the most popular puzzles in Japan.

One thing is for sure, Sudoku grows ever more popular everyday.