Inform lets an author write a new text adventure and turn it into a story file for an interpreter. Graham Nelson first released it in 1993, extending the creative life of the Z-machine beyond Infocom’s original commercial games.
Nelson’s Designer’s Manual explains a distinction at the centre of the system. The compiler translates the author’s program. The library supplies a parser, which interprets typed commands, and a world model, which represents places, objects and their usual behaviour.
Describe a world, then change its rules
An author can define rooms, put objects inside them and give those objects properties. A container might be openable; an object might provide light. Library rules handle many ordinary interactions, while the author adds behaviour for the particular game.
That makes a command more than a text match. Taking a key changes the model of where it is; later descriptions and actions can respond to that changed state. The manual separates the player’s words, the action they request and the rules which decide what follows.
The language changed
Nelson’s announcement of Inform 7, dated 30 April 2006, looks back to Inform 1’s release on the same date in 1993 and Inform 6’s in 1996. It presents Inform 7 as a redesigned application using a notation closer to written English, rather than a small syntax revision to Inform 6.
The older language continued to matter. When the Interactive Fiction Technology Foundation took over hosting the Inform 6 site in 2018, Andrew Plotkin explained that people still wrote directly in it and that it remained part of Inform 7’s toolchain. The preserved site is historical documentation, not a current download catalogue.
Inform’s importance lies in both parts: a language for authors’ particular ideas, and shared machinery for the many responses a player might try. TADS provides another extensive adventure-writing system; DAAD approaches portability through its own adventure databases and machine-specific interpreters.
Sources
- Graham Nelson, The Inform Designer’s Manual, fourth edition: Fourth edition, 2001; introduction and chapters II–V and VII explain compiler/library roles, parser, world model and target machine.
- Graham Nelson, Inform 7: Public Beta: Original public announcement, 30 April 2006; Inform 1/6 chronology and Inform 7’s different notation and application.
- Andrew Plotkin, The Inform 6 web site is now hosted at IFTF: Custodian’s announcement, 23 August 2018; preservation of the Inform 6 site and its continued use within Inform 7.