Undocumented feature

Undocumented features are frequently found in software releases. They are often elements of the software not intended for use by everyday end users, but left available for use by software support and knowledgeable end users who have learned of them through user groups or mailing lists.

Since the suppliers of the software consider that the software documentation constitutes a contract for the behavior of the software, undocumented features are generally left unsupported, and may be removed or changed at will and without notice to the users. This makes using undocumented features a two-edged sword.

Oddly, the undocumented feature itself became a major feature of computer games. Developers included various "cheats" and other special features that were not explained in the packaged material, but became part of the "buzz" about the games on the Internet and among gamers.

Of course, in some cases, the feature was intended to be documented, but wasn't. In other cases, software bugs are referred to jokingly as undocumented features. ("It's not a bug, it's an undocumented feature!")