This book is the second book in the Series to teach how to solve Sudoku puzzles. Included, 500 RELAXING (moderate level, a little tougher than the 1st book in the series, EASY) puzzles with Solutions.. The audience would be those recently discovering Sudoku, young to old, and teachers (especially 4th to 5th grade) who are ready to use some of the basic Sudoku solving strategies in a more challenging puzzle. Have fun.