This pocket-sized guide to the biggest craze for Summer 2005 features:

* Easy to follow illustrated instructions

* Guidance on how to play the game and different strategies to tackle the puzzles

* 240 addictive new puzzles from basic to fiendish

This guide is perfect for newcomers to Su Doku as well as experienced Su Doku players looking to improve their game and addicts who just can't get enough new puzzles

Su Doku (or Sudoku) has been dubbed the Rubik's Cube of the 21st century, it's a cryptic and highly addictive puzzle that involves inserting numbers in a 9x9 grid and making sure that every row and every column and every 3x3 box within the bigger grid contains all the digits from one to nine.

All it takes is the ability to identify the numerals 1-9, a sense for logic, a methodical cast of mind and a large measure of application to boot. You can get better and quicker, if you put your mind to it. And there is no predicting who will excel: you can be a disaster at maths and a whiz at Su Doku