Soduko Rules

The rules of Sudoku are simply that you must fill in the empty squares in the Sudoku grid so that every column, every row and every 3x3 sub-grid contain all the numbers 1 to 9 once.

A completed puzzle is correct when the number from 1 to 9 appear once in each "direction" (horizontal, vertical and 3x3 sub-grid). Sounds simple? Well yes the easy puzzles can be solved pretty quickly once you've been playing a while but more complicated puzzles can be extremely difficult.