It is also the inspiration for the Marvel Database Project.
Jim Shooter, Marvel's then Editor in Chief, initially came up with the idea for the project, envisioning a guide detailing statistics much in the manner of those found upon the backs of baseball cards. This initial project was to be called The Marvel Super-Specifications Handbook. He appointed Mark Gruenwald editor of the project, and in Gruenwald's hands the project gained its published name and also grew in scope to cover all aspects of the Marvel Universe, although Gruenwald himself noted it was not comprehensive.
Critics of the handbook have argued that the level of detail within the guide effectively limited the ability of writers to innovate, a charge Gruenwald dismissed, reputedly stating that the information presented was only the most recent data and was subject to change. Peter Sanderson, one of the writers of the original guide, noted that "Mark sought to make the Marvel characters' super-powers as firm a basis in real science as possible. After the first version of the Handbook, Mark decided that some of the explanations had grown too complicated, and asked me to simplify them."
The OHOTMU detailed the more significant characters, items and locations in the Marvel Universe, itemizing them into individual entries. Individual entries consisted, in most cases, of:
In the original OHOTMU, characters were listed at one character per page, although minor characters were sometimes listed at two to a page and major characters would occasionally receive more than one page. In the Deluxe Edition, however, every character received at least one page; the most significant characters such as Captain America or Iron Man could receive up to 3-5 pages for their writeups; less important characters, such as Sunspot or Volcana, typically received one or two pages.
In the Master Edition (1990-1993) this reverted and every character, major or minor, was given the same amount of space - both sides of single loose leaf page. In the latest (2004- ) version this has been changed back again and now characters receive different lengths of entry depending on their history and importance.
There have been many iterations of the OHOTMU concept since it was first launched in 1982:
The OHOTMUDE is the most familiar version of the OHOTMU to fans as it was distributed more widely and was of a more reasonable price than the OHOTMU Master Edition. Its trade paperback version is also the most durable OHOTMU available. Unfortunately, it is currently almost two decades out of date, the last issue having been released in 1988.
In addition to the Marvel Universe, Marvel published a number of handbook-style products for their licensed properties, among them Conan the Barbarian (The Official Handbook to the Conan Universe), G.I. Joe (G.I. Joe Order of Battle) and the Transformers (Transformers Universe).
It is amusing to note that in certain humor-based Marvel publications, such as What The--?!, "Ohotmu" has been used as the name of a parody version of a Watcher, as a play on the Watchers' reputations as far-seeing and possessing of great knowledge and for the phonetic pronunciation of OHOTMU (most often "oh-hot-moo") sounding similar to the name of the best-known Watcher, Uatu ("oo-wa-two").
Bibliography of Official Handbook series
The Official Handbook of the Marvel Universe Vol. I