Halo Story Bible
- "It is the ponderous collection of lies, damned lies, and half-truths from which the entire Halo Universe is constructed."
- —Robert McLees 
The Halo Story Bible, created by Bungie Studios, is the single most important object to the development of the Halo universe. The "Story Bible" is made up of many pieces of information, most of which is readily available to the fans.
The Story Bible is the most extensive collection of material for the Halo universe, and, to date, is also the single most secretive thing Bungie holds. The Story Bible contains background information, technical data, and other details about canon-related topics that have not been mentioned anywhere else.
Consisted of four black-and-silver looseleaf binders, the Story Bible is under the care of Frank O'Connor of 343 Industries. When the Story Bible is not with O'Connor, it is stored in a locked metal cabinet in the studio's offices, which are inaccessible to the rest of Microsoft. Eric Nylund, writer of three Halo novels, commented in a letter to Halopedia that the Story Bible was given to him during the writing of the books and quickly taken back once the novels were complete. Some less-sensitive material from the Story Bible was published in the Halo: Combat Evolved: Sybex Official Strategies & Secrets strategy guide. Various portions of the Story Bible, including weapon- and vehicle-related information, have been posted on Bungie.net as well. The Halo Encyclopedia also contains new information on canon, and some of its content originated from the Story Bible.
It is apparent that the material in the Story Bible is not entirely static, as the Kig-yar homeworld of Eayn is a fictional satellite of a real extrasolar planet, HD 69830 d, that was not discovered until May 2006.
In a keynote speech at the 2013 D.I.C.E. Summit, Frank O'Connor said "...people often talk about the Halo Story Bible as if it's this secret dusty tome that we have hidden away and it's really a collection of things and I'd say about eighty-five percent of those are available to everybody to read and watch or experience and ingest and they're a super valuable communication tool for us internally as well as externally."
- The binders are black and silver, and it weighs 10 lbs (including the contents).
- During a private question and answer session, Martin O'Donnell jokingly claimed that he had memorized every chapter and verse of the Halo Story Bible.
- On February 12th, 2010, both Martin O'Donnell and Frank O'Connor joined host Chris Cashman in his booth during a special session of 1 vs 100. When answering a fan's question about continuity in the Halo universe, both of them jokingly referred to the Halo Story Bible.