Sudoku - 200 Very Easy to Master Puzzles 9x9 (Volume 13)

Sudoku (originally called Number Place) is a logic-based combinatorial number-placement puzzle. The objective is to fill a 9 9 grid with digits so that each column, each row, and each of the nine 3 3 subgrids that compose the grid (also called 'boxes', 'blocks', 'regions', or 'subsquares') contains all of the digits from 1 to 9. The puzzle setter provides a partially completed grid, which for a well-posed puzzle has a unique solution.