From the back cover:
Meet the dark races, the foul races, the evil races; the Orcs, Kobolds, Goblins, Gnolls and Trolls. Learn how they live, hate, and terrorize. Each dark race is described in detail with complete towns, villages, fortresses, dungeons and featuring Orcish Culture a special article written by Robert Lynn Aspirin.
Also included are adventures involving each of the dark folk that are suitabe for use with all popular role playing systems including Advanced Dungeons and Dragons.
Bring depth to the villains in your world.