Spacing Guild
"The Dune Encyclopedia", written by McNelly and 42 other contributors as a companion to the "Dune" series, was published in paperback in 1984. It describes in great detail many aspects of the "Dune" universe not found in the novels themselves, such as biographies of the major characters, the languages of Fremen, Galach, and Spacing Guild (including alphabets and pronunciation), and shortened summaries of the plots of the novels. The encyclopedia also includes explanations of the armies, major schools (Bene Gesserit, Mentats, etc.), and major industries (including the spice melange), as well as descriptions of future technologies and artwork on the major characters and concepts of the novels.