The design and concept of "EverQuest" is heavily indebted to text-based MUDs, in particular DikuMUD, and as such "EverQuest" is considered a 3D evolution of the text MUD genre like some of the MMOs that preceded it, such as "Meridian 59" and "The Realm Online". John Smedley, Brad McQuaid, Steve Clover and Bill Trost, who jointly are credited with creating the world of "EverQuest", have repeatedly pointed to their shared experiences playing MUDs such as "Sojourn" and "TorilMUD" as the inspiration for the game. Famed book cover illustrator Keith Parkinson created the box covers for earlier installments of "EverQuest".