View source for Inform

{{short description|Programming language and design system}}
{{About|the programming language}}
{{Use mdy dates|date=October 2014}}
{{Infobox software
| name                   = Inform
| logo                   = [[File:Inform 7 IDE Icon.png]]<!-- FAIR USE: Low resolution icon for program, for identification purposes. -->
| screenshot             = 
| caption                = 
| author                 = [[Graham Nelson]]
| developer              = [[Graham Nelson]]
| released               = 
| latest release version = 10.1.2
| latest release date    = {{start date|2022|08|31}}<ref>{{cite web
  | url        = https://github.com/ganelson/inform/blob/master/notes/release/10-1-0.md
  | title      = Release notes for Inform v10.1.0 and v10.1.1
  | access-date = 2022-08-26
  | publisher  = github.com
  }}</ref>
| latest preview version = 
| latest preview date    = 
| operating system       = [[Microsoft Windows]], [[macOS|Mac OS X]], [[Linux]], others
| platform               = 
| status                 = 
| genre                  = [[Interactive fiction]] development and play
| license                = [[Artistic License|Artistic 2.0]]<ref>{{cite web|url=https://intfiction.org/t/inform-7-v10-1-0-is-now-open-source/55674|title=Inform 7 v10.1.0 is now open-source|date=April 28, 2022 |access-date=April 28, 2022}}</ref>
| website                = https://ganelson.github.io/inform-website/
}}
'''Inform''' is a [[programming language]] and design system for [[interactive fiction]] originally created in 1993 by [[Graham Nelson]]. Inform can generate programs designed for the [[Z-machine|Z-code]] or [[Glulx]] virtual machines. Versions 1 through 5 were released between 1993 and 1996. Around 1996, Nelson rewrote Inform from [[first principle]]s to create version 6 (or '''Inform 6''').<ref name="spag44">{{cite web
  | url        = http://www.spagmag.org/archives/backissues/SPAG44
  | title      = The SPAG Interview: Graham Nelson and Emily Short on Inform 7
  | access-date = 2015-11-07
  | date       = 2006-04-30
  | work       = SPAG #44
  | publisher  = The Society for the Promotion of Adventure Games
  }}</ref> Over the following decade, version 6 became reasonably stable and a popular language for writing interactive fiction. In 2006, Nelson released '''Inform 7''' (briefly known as '''Natural Inform'''), a completely new language [[Natural language programming|based on principles of natural language]] and a new set of tools based around a book-publishing metaphor.

== Z-Machine and Glulx ==

The Inform compilers translate Inform code to story files for [[Glulx]] or [[Z-machine|Z-code]], two [[virtual machine]]s designed specifically for interactive fiction. Glulx, which can support larger games, is the default.

The Z-machine was originally developed by [[Infocom]] in 1979 for their interactive fiction titles.  Because there is at least one such interpreter for nearly every major and minor platform, this means that the same Z-code file can be run on a multitude of platforms with no alterations. Originally Inform targeted the Z-machine only.

[[Andrew Plotkin]] created an unofficial version of Inform 6 that was also capable of generating files for [[Glulx]], a virtual machine he had designed to overcome many of the limitations of the several-decades-old Z-machine. Starting with Inform 6.3, released February 29, 2004, Inform 6 has included official support for both virtual machines, based on Andrew Plotkin's work.  Early release of Inform 7 did not support Glulx, but in August 2006 Glulx support was released.

== Inform 6 ==

{{Infobox programming language
| name                   = Inform 1–6
| logo                   = 
| paradigm               = [[Object-oriented programming|object-oriented]], [[Procedural programming|procedural]]
| year                   = 1993
| designer               = [[Graham Nelson]]
| developer              = [[Graham Nelson]]
| latest_release_version    = 6.42
| latest_release_date       = {{start date|2024|02|10}} <ref name="IN6repo">{{cite web
  | url        = https://github.com/DavidKinder/Inform6/releases/tag/v6.42
  | title      = Release Inform 6.42
  | website = [[GitHub]]
  | access-date = 2024-12-04
  }}</ref>
| typing                 = 
| implementations        = 
| dialects               = 
| influenced_by          = [[Z-machine]], [[C (programming language)|C]]<ref name=Plotkin>{{cite web |last1=Plotkin |first1=Andrew |title=What is ZIL anyway? |url=http://blog.zarfhome.com/2019/04/what-is-zil-anyway.html |website=Zarf |language=en |date=April 17, 2019|quote=I6 follows C very closely, in this example.}}</ref>

| influenced             = Inform 7
| operating_system       = [[Microsoft Windows]], [[macOS|Mac OS X]], [[Linux]], others
| license                = [[Freeware]] and [[Artistic License]] 2.0
| website                = {{URL|https://inform-fiction.org/}}
}}

Inform was originally created by [[Graham Nelson]] in 1993.  In 1996 Nelson rewrote Inform from first principles to create version 6 (or Inform 6). Over the following decade, version 6 became reasonably stable and a popular language for writing interactive fiction.

The Inform 6 system consists of two major components: the '''Inform compiler''', which generates story files from Inform source code, and the '''Inform library''', a suite of software which handles most of the difficult work of [[parsing]] the player's text input and keeping track of the world model. The name Inform also refers to the '''Inform programming language''' that the compiler understands.

Although Inform 6 and the Z-Machine were originally designed with interactive fiction in mind, many other programs have been developed, including a [[BASIC]] interpreter, a [[LISP (programming language)|LISP]] tutorial (complete with interpreter), a [[Tetris]] game, and a version of the game [[Snake (1998 video game)|Snake]].

=== The Inform 6 compiler ===

The Inform [[compiler]] generates files for the [[Z-machine]] or [[Glulx]] (also called story files) from Inform 6 [[source code]].

=== The Inform 6 programming language ===

The Inform programming language is [[Object-oriented programming|object-oriented]] and [[procedural programming|procedural]]. A key element of the language is objects. Objects are maintained in an object tree which lists the parent–child relationships between objects. Since the parent–child relationship is often used to represent location, an object which is the parent of another object is often said to "hold" it. Objects can be moved throughout the tree. Typically, top level objects represent rooms and other locations within the game, which may hold objects representing the room's contents, be they physical items, non-player characters, the player's character, or background effects. All objects can hold other objects, so a <code>livingroom</code> object might hold an <code>insurancesaleman</code> object which is holding a <code>briefcase</code> object which contains the <code>insurancepaperwork</code> object.

In early versions of Inform, objects were different from the notion of objects from object-oriented programming, in that there was no such thing as a class. Later versions added support for class definitions and allowed objects to be members of classes. Objects and classes can inherit from multiple classes. Interactive fiction games typically contain many unique objects. Because of this, many objects in Inform do not inherit from any class, other than the "metaclass" Object. However, objects very frequently have attributes (boolean properties, such as <code>scenery</code> or <code>edible</code>) that are recognized by the Inform library. In other languages this would normally be implemented via inheritance.

Here is a simple example of Inform 6 source code.
<syntaxhighlight lang="inform6">
! Square brackets define a routine. This is the Main routine, which takes no arguments.
[ Main;
    print "Hello, World!^";
];
</syntaxhighlight>

The procedual parts, statements and operators, are largely borrowed from C, with the notable exception that {{code|-->x}} instead of {{code|[x]}} is used to take array subscripts. Routines are defined in square brackets, as in the {{code|Main}} routine above,<ref name=Plotkin/> but called with round brackets as in C. The character {{code|@}} is used to [[escape character]]s and to invoke raw Z-machine opcodes.<ref>{{cite web |title=The Inform Designer's Manual, v4, Contents |url=https://www.inform-fiction.org/manual/html/contents.html |website=www.inform-fiction.org}}</ref>

=== Inform 6 library ===

The Inform system also contains the Inform library, which automates nearly all the most difficult work involved in programming [[interactive fiction]]; specifically, it includes a text [[parsing|parser]] that makes sense of the player's input, and a world model that keeps track of such things as objects (and their properties), rooms, doors, the player's inventory, etc.

The Inform compiler does not require the use of the Inform library. There are several replacement libraries available, such as Platypus<ref name="platypus">{{cite web
  | url        = http://www.elvwood.org/InteractiveFiction/Platypus/
  | title      = Inform Platypus release 4
  | access-date = 2007-01-04
  | date       = 2002-03-14
  | last       = Turner
  | first      = Anson
}}</ref> and [[InformATE]], a library that codes Inform in Spanish. Some games may use no library at all, such as a direct port of [[Zork]] into Inform 6.<ref name=Plotkin/>

=== Example game ===
{{missing information|section|C-like logic parts|date=January 2023}}
Here is an example of Inform 6 source code that makes use of the Inform library. The Inform 6 code sample below is usable in Inform 7, but not without special demarcation indicating that it is embedded legacy code.

<syntaxhighlight lang="inform6">
Constant Story "Hello Deductible";
Constant Headline "^An Interactive Example^";

Include "Parser";
Include "VerbLib";

[ Initialise;
    location = Living_Room;
    "Hello World";
];

Object Kitchen "Kitchen";
Object Front_Door "Front Door";

Object Living_Room "Living Room"
    with
        description "A comfortably furnished living room.",
        n_to Kitchen,
        s_to Front_Door,
    has light;

Object -> Salesman "insurance salesman"
    with
        name 'insurance' 'salesman' 'man',
        description "An insurance salesman in a tacky polyester
              suit.  He seems eager to speak to you.",
        before [;
            Listen:
                move Insurance_Paperwork to player;
                "The salesman bores you with a discussion
                 of life insurance policies.  From his
                 briefcase he pulls some paperwork which he
                 hands to you.";
        ],
    has animate;

Object -> -> Briefcase "briefcase"
    with
        name 'briefcase' 'case',
        description "A slightly worn, black briefcase.",
    has container;

Object -> -> -> Insurance_Paperwork "insurance paperwork"
    with
        name 'paperwork' 'papers' 'insurance' 'documents' 'forms',
        description "Page after page of small legalese.";

Include "Grammar";
</syntaxhighlight>

=== Notable games developed in Inform 6 or earlier versions ===
* ''[[Curses (video game)|Curses]]'', by [[Graham Nelson]] (1993), the first game ever written in the Inform programming language. Considered one of the first "modern" games to meet the high standards set by Infocom's best titles.<ref name="highprogrammer-Curses">{{cite web
  | author     = Alan De Smet
  | date       = 2006-03-14
  | url        = http://www.highprogrammer.com/alan/rants/reviews/video_games/if/curses.html
  | title      = Curses (Interactive Fiction Reviews)
  | access-date = 2006-11-01
  }}</ref>
* ''[[Zork: The Undiscovered Underground]]'' (1997), written by [[Marc Blank]] & [[Michael Berlyn]], programmed by Gerry Kevin Wilson. Given away free by [[Activision]] to promote the release of ''[[Zork: Grand Inquisitor]]''.
* ''[[Anchorhead]]'', by Michael S. Gentry (1998) is a highly rated horror story inspired by [[H. P. Lovecraft]]'s [[Cthulhu Mythos]].<ref name="ifratings-anchorhead">Of the 1219 games rated at "Interactive Fiction Ratings", Anchorhead was the highest rated game as of January 4, 2007. ({{cite web
  | url        = http://www.carouselchain.com/if/statistics.php
  | title        = IF Rating Stats
  | access-date        = 2007-01-04
  | archive-date        = May 11, 2008
  | archive-url        = https://web.archive.org/web/20080511194344/http://www.carouselchain.com/if/statistics.php
  | url-status        = dead
  }})</ref>
* ''[[Photopia]]'', by [[Adam Cadre]] (1998), the first almost entirely puzzle-free game. Won the annual [[Interactive Fiction Competition]] in 1998.
* ''[[Varicella (video game)|Varicella]]'' by Adam Cadre (1999). It won four [[XYZZY Award]]s in 1999 including the XYZZY Award for Best Game, and had a scholarly essay written about it.<ref name="montfort">{{cite web
  | archive-url  = https://www.webcitation.org/5c8jC0dFt?url=http://www.mit.edu/~montfort/Varicella.pdf
  | archive-date = 2009-11-06
  | url         = https://www.mit.edu/~montfort/Varicella.pdf
  | title       = Face It, Tiger, You Just Hit the Jackpot: Reading and Playing Cadre's Varicella
  | access-date  = 2009-11-06
  | date        = August 2003
  | last        = Montfort
  | first       = Nick
  | author2     = Stuart Moulthrop
  }}
Published as {{Cite journal
  | last1        = Montfort
  | first1       = Nick
  | last2       = Moulthrop
  | first2      = Stuart
  | title       = Face It, Tiger, You Just Hit the Jackpot: Reading and Playing Cadre's Varicella
  | periodical  = Fine Art Online
  | publisher   = [[Mississippi State University]]
  | date        = August 2003
  | volume      = 17
  | issue       = 8
  | url         = http://www.msstate.edu/Fineart_Online/Backissues/Vol_17/faf_v17_n08/reviews/montfort.html
  | archive-url  = https://web.archive.org/web/20071013191103/http://msstate.edu/Fineart_Online/Backissues/Vol_17/faf_v17_n08/reviews/montfort.html
  | archive-date = 2007-10-13
  }}</ref>
* ''[[Galatea (video game)|Galatea]]'', by [[Emily Short]] (2000).  Galatea is focused entirely on interaction with the animated statue of the same name.  Galatea has one of the most complex interaction systems for a [[non-player character]] in an interactive fiction game. Adam Cadre called Galatea "the best NPC ever".<ref name="avventuretestuali">{{cite web
  | url        = http://www.avventuretestuali.com/interviste/cadre-eng
  | title      = Photopia is a short story, Varicella is a world
  | access-date = 2007-01-04
  | date       = January 2002
  | work       = L’avventura è l’avventura
  }}</ref>
* ''[[Slouching Towards Bedlam]]'', by Star C. Foster and Daniel Ravipinto (2003).  Set in a [[steampunk]] setting, the game narratively integrates meta-game functionality (saving, restoring, restarting) into the game world itself.  The game won two [[XYZZY Award]]s and received the highest average score of any game in the [[Interactive Fiction Competition]] as of 2006.

== Inform 7 ==

{{Infobox programming language
| name                   = Inform 7
| logo                   = [[File:Inform 7 IDE Icon.png]]<!-- FAIR USE: Low resolution icon for program, for identification purposes. -->
| paradigm               = [[Natural-language programming|natural-language]], [[Declarative programming|declarative]],  [[Procedural programming|procedural]]
| year                   = 2006
| designer               = [[Graham Nelson]]
| developer              = [[Graham Nelson]]
| latest release version = 10.1.2
| latest release date    = {{start date|2022|08|31}}<ref>{{cite web
  | url        = https://github.com/ganelson/inform/blob/master/notes/release/10-1-0.md
  | title      = Release notes for Inform v10.1.0 and v10.1.1
  | access-date = 2022-08-26
  | publisher  = github.com
  }}</ref>
| latest_test_version    = 
| latest_test_date       = 
| typing                 = 
| implementations        = 
| dialects               = 
| influenced_by          = Inform 6, [[Natural-language programming]]
| influenced             = 
| operating_system       = [[Microsoft Windows]], [[macOS|Mac OS X]], [[Linux]], others
| license                = [[Freeware]] (before 2022); [[Artistic License]] 2.0 (since 2022)
| website                = http://inform7.com/
}}

On April 30, 2006, Graham Nelson announced the beta release of Inform 7 to the rec.arts.int-fiction newsgroup.<ref name="raif">{{cite newsgroup
  | title      = Inform 7: Public Beta
  | author     = Graham Nelson
  | date       = 2006-04-30
  | newsgroup  = rec.arts.int-fiction
  | message-id = 1146419288.944486.157150@i39g2000cwa.googlegroups.com
  | url        = https://groups.google.com/group/rec.arts.int-fiction/msg/17791dfefeec46e0
  | access-date = 2007-01-04
}}</ref> Inform 7 consists of three primary parts: The '''Inform 7 [[Integrated development environment|IDE]]''' with development tools specialized for testing interactive fiction, the '''Inform 7 compiler''' for the new language, and "'''The Standard Rules'''" which form the core library for Inform 7.  Inform 7 also relies on the '''Inform library''' and '''Inform compiler''' from Inform 6.   The compiler compiles the Inform 7 source code into Inform 6 source code, which is then compiled separately by Inform 6 to generate a [[Glulx]] or [[Z-machine|Z-code]] story file.  Inform 7 also defaults to writing [[Blorb]] files, archives which include the Z-code together with optional "cover art" and metadata intended for indexing purposes. The full set of Inform 7 tools are currently available for [[macOS|Mac OS X]], [[Microsoft Windows]] and [[Linux]] (since 2007).

{{As of|2023}}, Inform 7 and its and tools remain under development.<ref name="jan07short">{{cite newsgroup
 |title      = Inform 7: Possible future developments
 |author     = Emily Short
 |date       = 2007-02-18
 |newsgroup  = rec.arts.int-fiction
 |message-id = 1169164007.311210.64650@a75g2000cwd.googlegroups.com
 |url        = https://groups.google.com/group/rec.arts.int-fiction/msg/980b5a84e8dfc29b
 |access-date = 2007-03-30
}}
Also archived at
{{cite web
 |url          = http://www.inform-fiction.org/I7Downloads/Documents/January2007Document.txt
 |title        = Inform 7: Possible future developments
 |date         = January 2007
 |last         = Short
 |first        = Emily
 |author2      = Graham Nelson
 |author2-link      = Graham Nelson
 |author-link   = Emily Short
 |access-date  = March 31, 2007
 |archive-url  = https://web.archive.org/web/20080905103637/http://www.inform-fiction.org/I7Downloads/Documents/January2007Document.txt
 |archive-date = September 5, 2008
 |url-status   = dead
}}</ref> Since April 2022, Inform 7 is open source and developed on [[GitHub]].<ref>{{cite web |last1=Nelson |first1=Graham |title=Inform 7 Version History |website=[[GitHub]] |url=https://github.com/ganelson/inform/blob/master/notes/version_history.md |date=13 January 2023}}</ref>

Inform 7 was named '''Natural Inform''' for a brief period of time, but was later renamed Inform 7. This old name is why the Inform 7 compiler is named "NI".<ref name="whyni">{{cite newsgroup
  | title      = Re: "Inform 7" is the wrong name
  | author     = Graham Nelson
  | date       = 2007-03-30
  | newsgroup  = rec.arts.int-fiction
  | message-id = 1175250734.801804.199340@y80g2000hsf.googlegroups.com
  | url        = https://groups.google.com/group/rec.arts.int-fiction/msg/b0424047b4038cd9
  | access-date = 2007-03-30
}}</ref>

=== Inform 7 IDE ===

[[File:Inform 7 code and skein.png|right|thumb|The Inform 7 IDE on [[macOS|Mac OS X]] showing source code and the skein]]<!-- FAIR USE: Screenshot of the software in question for identification and illustration.  Furthemore, software in question is under GPL, while screenshot itself is released under public domain. -->
[[File:Inform 7 map and transcript.png|right|thumb|The Inform 7 IDE on Mac OS X showing the Index Map and the transcript]]<!-- FAIR USE: Screenshot of the software in question for identification and illustration.  Furthemore, software in question is under GPL, while screenshot itself is released under public domain. -->

Inform 7 comes with an integrated development environment (IDE) for Mac OS X, Microsoft Windows and Linux. The Mac OS X IDE was developed by Andrew Hunter. The Microsoft Windows IDE was developed by David Kinder. The Linux IDE (known as GNOME Inform) was developed by Philip Chimento.<ref name="gnomei7">{{cite web
  | url   = http://sourceforge.net/projects/gnome-inform7/
  | title = GNOME Inform 7 SourceForge project page
  | date  = February 2008
  }} &ndash; Now moved to GitHub at {{cite web |last1=Chimento |first1=Philip |title=ptomato/inform7-ide |website=[[GitHub]] |url=https://github.com/ptomato/inform7-ide |date=27 December 2022}}</ref>

The Inform 7 IDE includes a text editor for editing Inform 7 source code. Like many other programming editors it features syntax highlighting. It marks quoted strings in one color. Headings of organizational sections (Volumes, Books, Chapters, Parts, and Sections) are bolded and made larger. Comments are set in a different color and made slightly smaller.

The IDE includes a built-in [[z-machine|Z-code]] interpreter. The Mac OS X IDE's interpreter is based on the Zoom interpreter by Andrew Hunter, with contributions from Jesse McGrew.{{Citation needed|date=April 2008}} The Microsoft Windows IDE's interpreter is based on [[WinFrotz]].

As a developer tests the game in the built-in interpreter, progress is tracked in the "skein" and "transcript" views of the IDE. The skein tracks player commands as a tree of branching possibilities. Any branch of the tree can be quickly re-followed, making it possible to retry different paths in a game under development without replaying the same portions of the game. Paths can also be annotated with notes and marked as solutions, which can be exported as text walkthroughs.  The transcript, on the other hand, tracks both player commands and the game's responses. Correct responses from the game can be marked as "blessed". On replaying a transcript or a branch of the skein, variations from the blessed version will be highlighted, which can help the developer find errors.

The IDE also provides various indices into the program under development.  The code is shown as a class hierarchy, a traditional IF map, a book-like table of contents, and in other forms.  Clicking items in the index jumps to the relevant source code.

The IDE presents two side-by-side panes for working in. Each pane can contain the source code being worked on, the current status of compilation, the skein, the transcript, the indices of the source code, a running version of the game, documentation for Inform 7 or any installed extensions to it, or settings. The concept is to imitate an author's manuscript book by presenting two "facing pages" instead of a multitude of separate windows.<ref name="raif" />

=== Inform 7 programming language ===

Notable features include strong bias towards declarative rule-based style of programming and ability to infer types and properties of objects from the way they are used. For example, the statement "John wears a hat." creates a "person" called "John" (since only people are capable of wearing things), creates a "thing" with the "wearable" property (since only objects marked "wearable" are capable of being worn), and sets John as wearing the hat.

Another notable aspect of the language is direct support for relations which track associations between objects.  This includes automatically provided relations, like one object containing another or an object being worn, but the developer can add their own relations. A developer might add relations indicating love or hatred between beings, or to track which characters in a game have met each other.

Inform 7 is a highly [[domain-specific programming language]], providing the writer/programmer with a much higher level of abstraction than Inform 6, and highly readable resulting source code. General-purpose logical and arithmetic statements are written in natural language (see e.g. the "Physics" example in ''The Inform Recipe Book'').<ref>{{cite web |title=10.1. Gases |url=https://ganelson.github.io/inform-website/book/RB_10_1.html |website=ganelson.github.io}}</ref>

In early Inform 7, the compiler translates the code to Inform 6, much like [[CFront]] did with C++ and C.<ref name="whyni"/> The current compiler (as of version 10 of 2022) is additionally able to translate the code directly to C for a native executable,{{dubious|reason=Source is vague. It *feels* more like a inweb "literary programming" situation if you look at the "foundation" code which uses it.|date=January 2023}} and to generate an "index mini-website" describing the story.<ref>{{cite web |title=Structure of the Inform 7 compiler |url=https://ganelson.github.io/inform/structure.html |website=ganelson.github.io}}</ref>

=== Example game ===

Statements in Inform 7 take the form of complete sentences. Blank lines and indentation are in some places structurally significant. The basic form of an Inform 7 program is as follows:

<syntaxhighlight lang="inform7" style="background-color:#F9F9F9; line-height:1.1em; ">
"Hello, World!" by "I.F. Author"

The world is a room.

When play begins, say "Hello, World!"
</syntaxhighlight>

The following is a reimplementation of the above "Hello Deductible" example written in Inform 7. It relies on the library known as "The Standard Rules" which are automatically included in all Inform 7 compilations.

<syntaxhighlight lang="inform7" style="background-color:#F9F9F9; line-height:1.1em; ">
"Hello Deductible" by "I.F. Author"

The story headline is "An Interactive Example".

The Living Room is a room. "A comfortably furnished living room."
The Kitchen is north of the Living Room.
The Front Door is south of the Living Room.
The Front Door is a door. The Front Door is closed and locked.

The insurance salesman is a man in the Living Room. The description is "An insurance salesman in a tacky polyester suit. He seems eager to speak to you." Understand "man" as the insurance salesman.

A briefcase is carried by the insurance salesman. The description is "A slightly worn, black briefcase."  Understand "case" as the briefcase.

The insurance paperwork is in the briefcase. The description is "Page after page of small legalese." Understand "papers" or "documents" or "forms" as the paperwork.

Instead of listening to the insurance salesman: 
	say "The salesman bores you with a discussion of life insurance policies. From his briefcase he pulls some paperwork which he hands to you.";
	move the insurance paperwork to the player.
</syntaxhighlight>

=== Notable games written in Inform 7 ===

''Mystery House Possessed'' (2005), by [[Emily Short]],<ref name="turbulence">{{cite web
  | url        = http://www.turbulence.org/Works/mystery/games.php
  | title        = Mystery House Taken Over
  | access-date        = 2007-01-04
  | archive-date        = May 4, 2006
  | archive-url        = https://web.archive.org/web/20060504184514/http://turbulence.org/Works/mystery/games.php
  | url-status        = dead
  }}</ref> was the first Inform 7 game released to be public. It was released as part of the "Mystery House Taken Over" project.

On March 1, 2006, Short announced the release of three further games:<ref name="raif-games">{{cite newsgroup
  | title      = Three games in Inform 7
  | author     = Emily Short (at the request of Graham Nelson)
  | date       = 2006-03-01
  | newsgroup  = rec.games.int-fiction
  | message-id = 1141259182.610660.185360@p10g2000cwp.googlegroups.com
  | url        = https://groups.google.com/group/rec.games.int-fiction/msg/354c7965c0dea5d6
  | access-date = 2007-01-04
  }}</ref>
''Bronze''<ref name="bronze">{{cite web
  | url        = http://ifdb.tads.org/viewgame?id=9p8kh3im2j9h2881
  | title      = Bronze
  | access-date = 2007-01-04
  | year       = 2006
  | last       = Short
  | first      = Emily
  }}</ref> (an example of a traditional puzzle-intensive game) and ''Damnatio Memoriae''<ref name="damn">{{cite web
  | url        = http://ifdb.tads.org/viewgame?id=2103dabhxzxsraal
  | title      = Damnatio Memoriae
  | access-date = 2007-01-04
  | year       = 2006
  | last       = Short
  | first      = Emily
  }}</ref> (a follow-up to her award-winning Inform 6 game ''[[Savoir-Faire]]'') were joined by Graham Nelson's ''The Reliques of Tolti-Aph''<ref name="reliques">{{cite web
  | url        = http://ifdb.tads.org/viewgame?id=nnhm4yp172oivtd9
  | title      = The Reliques of Tolti-Aph
  | access-date = 2007-01-04
  | year       = 2005
  | last       = Nelson
  | first      = Graham
  }}</ref> (2006). When the Inform 7 public beta was announced on April 30, 2006, six "worked examples" of medium to large scale works were made available along with their source code, including the three games previously released on March 1.<ref name="bronze-ex">{{cite web
 |url         = http://inform-fiction.org/I7Downloads/Examples/bronze/
 |title       = Bronze
 |access-date  = 2007-01-04
 |year        = 2006
 |last        = Short
 |first       = Emily
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20070210003932/http://inform-fiction.org/I7Downloads/Examples/bronze/
 |archive-date = February 10, 2007
 |df          = mdy-all
}}</ref><ref name="damn-ex">{{cite web
 |url         = http://inform-fiction.org/I7Downloads/Examples/dm/
 |title       = Damnatio Memoriae
 |access-date  = 2007-01-04
 |year        = 2006
 |last        = Short
 |first       = Emily
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20061212185900/http://inform-fiction.org/I7Downloads/Examples/dm/
 |archive-date = December 12, 2006
 |df          = mdy-all
}}</ref><ref name="reliques-ex">{{cite web
 |url         = http://www.inform-fiction.org/I7Downloads/Examples/rota/
 |title       = The Reliques of Tolti-Aph
 |access-date  = 2007-01-04
 |year        = 2005
 |last        = Nelson
 |first       = Graham
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20070206202522/http://inform-fiction.org/I7Downloads/Examples/rota/
 |archive-date = February 6, 2007
 |df          = mdy-all
}}</ref>

Emily Short's ''[[Floatpoint]]'' was the first Inform 7 game to take first place in the [[Interactive Fiction Competition]].<ref>{{cite web
  | url        = http://www.ifcomp.org/comp06/
  | title      = 12th Annual Interactive Fiction Competition
  | access-date = 2007-05-12
  | year       = 2006
  }}</ref>
It also won 2006 [[XYZZY Award]]s for Best Setting and Best NPCs.<ref>{{cite web
 |url=http://www.xyzzynews.com/2006winners.html 
 |title=XYZZY Awards: Winning Games of 2006 
 |access-date=2007-05-12 
 |url-status=dead 
 |archive-url=https://web.archive.org/web/20070515062751/http://www.xyzzynews.com/2006winners.html 
 |archive-date=May 15, 2007 
 |df=mdy-all 
}}</ref> ''[[Rendition (text adventure game)|Rendition]]'', by nespresso (2007), is a [[experimental literature|political art experiment]] in the form of a text adventure game. Its approach to [[tragedy]] has been discussed academically by both the [[Association for Computing Machinery]]<ref>{{cite web
  | url   = http://www.natematias.com/cam/trag-elit/Emily-Short-Tragedy.pdf
  | title = ACM Hypertext 2007 conference slides (PDF)
  }}</ref> and [[Cambridge University]].<ref>{{cite web
  | url   = http://www.natematias.com/cam/trag-elit/TragPresentation.html
  | title = Cambridge University lecture slides
  }}</ref>{{bsn|reason=This is a Flash file. Modern browsers can't cope with Flash. Also this citation is inadequate: who exactly at the university? What was the title?|date=December 2024}}

== See also ==
* {{slink|Interactive fiction|Development systems}} lists software similar to Inform
* [[TADS]] The Text Adventure Development System (TADS), another leading IF development system

== Further reading ==
; Inform 6
* The official manual of Inform is [[Graham Nelson]]'s ''Inform Designer's Manual'': it is a tutorial, a manual, and a technical document rolled into one. It is available online for free at Inform's official website,<ref name="inform-fiction-dm4">{{cite web
  | url        = http://www.inform-fiction.org/manual/download_dm4.html
  | title      = Download the Inform Designer's Manual
  | access-date = 2007-01-04
  | date       = 2006-04-01
  }}</ref> and two printed editions are available: a softcover ({{ISBN|0-9713119-0-0}}) and a hardcover ({{ISBN|0-9713119-3-5}}).<ref>{{cite web
  | url        = http://www.inform-fiction.org/manual/about_dm4.html
  | title      = About the Inform Designer's Manual
  | access-date = 2007-01-04
  | date       = 2006-04-01
  }}</ref>
* The ''Inform Beginner's Guide'' by Roger Firth and Sonja Kesserich ({{ISBN|0-9713119-2-7}}) attempts to provide a more gentle introduction to Inform. It is available for free at Inform's official website.<ref name="inform-fiction=ibg">{{cite web
  | url        = http://www.inform-fiction.org/manual/download_ibg.html
  | title      = Download the Inform Beginner's Guide
  | access-date = 2007-01-04
  | date       = 2006-04-01
}}
{{cite web
  | url        = http://www.inform-fiction.org/manual/IBG.pdf
  | title      = The Inform Beginner's Guide: Third Edition
  | access-date = 2007-01-04
  | date       = August 2004
  | last       = Firth
  | first      = Roger
  | author2    = Sonja Kesserich
  }}</ref>
;Inform 7
*  The SPAG Interview - An interview with designers [[Graham Nelson]] and [[Emily Short]] about the development of Inform 7.  This interview was made shortly before its release and published on the same day as the initial release.<ref name="spag44" />
* "Natural Language, Semantic Analysis and Interactive Fiction" - A paper on the design of Inform 7 by designer [[Graham Nelson]].<ref name="nlsaif">{{cite journal
  | author     = Graham Nelson
  | title      = Natural Language, Semantic Analysis, and Interactive Fiction
  | date       = 2006-04-10
  | url     = http://inform7.com/learn/documents/WhitePaper.pdf
  | archive-url = https://web.archive.org/web/20180314185630/http://inform7.com/learn/documents/WhitePaper.pdf
  | url-status = dead
  | archive-date = 2018-03-14
  | access-date = 2007-01-04
  }}</ref>

== References ==
{{Reflist|2}}

== External links ==
* [http://www.firthworks.com/roger/cloak/inform/index.html Cloak of Darkness: Inform] {{Webarchive|url=https://web.archive.org/web/20160830143129/http://www.firthworks.com/roger/cloak/inform/index.html |date=August 30, 2016 }} presents the same, short game implemented in both Inform 6 and Inform 7, as well as other languages for comparison.
* [http://www.inform-fiction.org/inform6.html Inform 6] - Official web site
* [http://www.firthworks.com/roger/informfaq/index.html Inform 6 FAQ] {{Webarchive|url=https://web.archive.org/web/20161010073730/http://www.firthworks.com/roger/informfaq/index.html |date=October 10, 2016 }} at Roger Firth's IF Pages provides details on programming in Inform 6.
* [http://inform7.com/ Inform 7] - Official web site.
* [http://mirror.ifarchive.org/ The Interactive Fiction Archive] provides many Inform tools, examples, and library files.
* [http://playfic.com/ Playfic] is a web-based interface for creating and sharing new games using Inform 7.
* [http://www.guncho.com/ Guncho] is a multiplayer interactive fiction system based on Inform 7 with a combination of [[Multi-user dungeon|MUD]]-like and web-based interfaces.

[[Category:1993 software]]
[[Category:Domain-specific programming languages]]
[[Category:History of computing in the United Kingdom]]
[[Category:Interactive fiction engines]]
[[Category:Formerly proprietary software]]
[[Category:Free game engines]]
[[Category:Programming languages created in 1993]]
[[Category:Software using the Artistic license]]
[[Category:Video game development software]]