A typical Dungeons & Dragons game consists of an “adventure”, which is roughly equivalent to a single story. The DM can either design an original adventure, or follow one of the many pre-made adventures (also known as “modules”) that have been published throughout the history of Dungeons & Dragons. Published adventures typically include a background story, illustrations, maps and goals for PCs to achieve. Some include location descriptions and handouts. Although a small adventure entitled “Temple of the Frog” was included in the Blackmoor rules supplement in 1975, the first stand-alone D&D module published by TSR was 1978’s Steading of the Hill Giant Chief, written by Gygax.
A linked series of adventures is commonly referred to as a “campaign”. The locations where these adventures occur, such as a city, country, planet or an entire fictional universe, are referred to as “campaign settings” or “world”. D&D settings are based in various fantasy genres and feature different levels and types of magic and technology. Popular commercially published campaign settings for Dungeons & Dragons include Greyhawk, Dragonlance, Forgotten Realms, Mystara, Spelljammer, Ravenloft, Dark Sun, Planescape, Birthright, and Eberron.