Standard Sudoku grid

Usually the puzzle is a 9×9 grid, made up of 3×3 subgrids called ‘regions’. Some cells contain numbers and these are called ‘givens’. The object of the game is to fill in the empty cells so that each column, row and region contains the numbers 1-9 only once. In each of the three ’scopes’ or ‘directions’ each number occurs only once therefore, thus the ’single number’ implied by the name of the puzzle. There is no mathematical solution to the puzzle; it is completed more through logical reasoning. The level of difficulty has very little to do with the number of givens within a grid, it is more the positioning of the numbers as opposed to the quantity.