The Long List of Worldcons (often called simply the "Long List") is the official, definitive, fanhistorical list maintained by WSFS delineating basic information about every Worldcon held, including its year, number, name, site, gohs, chairman, attendance figures and other notes.
The list is compiled by the Long List Committee established by Noreascon 4 and subsequently endorsed each year by the WSFS Business Meeting. It is not technically a WSFS Committee, but acts as one in practice. It is also called the Formalization of Long Lists Committee (FOLLE).
The committee states:
Our philosophy is to create lists which accurately reflect reality without being so detailed that the main information is lost in a forest of subtle detail. To do this we have divided the Long List into two parts: The Long List itself and an extensive set of notes. We anticipate that the Long List will be printed in Worldcon Souvenir Books and the like, while the notes will typically only be referred to on-line. When multiple interpretations of a piece of data (who chaired a convention, what its name was, where it was held, etc.) exist, our policy is to have the Long List include the version which in our judgment best reflects the facts as understood by the people involved, and to document whatever variations or details we have discovered in the notes. We will respect historical judgments as long as they are not clearly in error, and we will attempt to objectively verify any corrections or notes we add.