Forgotten Realms
The "Campaign Set" (often referred to as the "Grey Box") was later released in 1987 as a boxed set of two source books ("Cyclopedia of the Realms" and "DM's Sourcebook of the Realms") and four large maps, designed by Greenwood in collaboration with author Jeff Grubb. The set introduced the campaign setting and explained how to use it, and reserved space on the map for SSI's Gold Box computer role-playing games set in the Forgotten Realms.
Forgotten Realms Adventures
"Forgotten Realms Adventures" is a revision of the "Forgotten Realms Sourcebook and Cyclopedia" material, taking into account the 2nd edition rules and the three years of Forgotten Realms products released up to that time. Among other things, this book cover the deities, secret societies, treasures, specific spells and magic rules of the campaign setting, as well as brief descriptions of the land and cities of the heartlands, with maps.