Book excerpt: The absolute, comprehensive, from Tiffany Aching to Jack Zweiblumen guide to all things Discworld, fully illustrated by Paul Kidby. The Discworld, as everyone knows, is a flat world balanced on the back of four elephants which, in turn, stand on the shell of the giant star turtle, the Great A'Tuin, as it slowly swims through space. It is also the global publishing phenomenon with sales of over 70 million books worldwide (but who's counting?). There's an awful lot of Discworld to keep track of. But fear not! Help is at hand. For the very first time, everything (and we mean everything) you could possibly want to know has been crammed into one place. If you need a handy guide to locales from Ankh-Morpork to Zemphis . . . If you can't tell your Achmed the Mads from your Jack Zweiblumens . . . If your life depends on distinguishing between the Agatean Empire and the Zoons . . . Look no further. Updated and perfected by Stephen Briggs, the man behind The Ultimate Discworld Companion's predecessor Turtle Recall, this is your ultimate guide to Sir Terry Pratchett's beloved fantasy world.