From the back:
"THE FIRST WORLD EVER MADE FOR THE AD&D GAME!
Return to the roots of fantasy roleplaying with the Player's Guide for the GREYHAWK campaign setting - the original ADVANCED DUNGEONS & DRAGONS game world! For newcomers as well as old-time fans, this book is the doorway to high adventure.
Enter the Flanaess - a crowded cluster of kingdoms and states, great and petty, struggling for survival and supremacy against one another and countless foes both internal and external. Learn about the nations and cities of the world of Greyhawk; the leaders and rebels that affect this war-torn land; the races that inhabit it and the creatures that threaten it. Use this book in conjunction with TSR's other GREYHAWK game accessories, or to begin your own campaign in the land that helped shape the AD&D game, the world that even now defines excitement and intrigue."