Editing Interactive fiction (section)

==Software==
===Development systems===
The original Interactive fiction Colossal Cave Adventure was programmed in [[Fortran]], originally developed by [[IBM]]. Adventure's parsers could only handle two-word sentences in the form of verb-noun pairs.

[[Infocom]]'s games of 1979–88, such as [[Zork]], were written using a [[LISP]]-like programming language called ZIL (Zork Implementation Language or Zork Interactive Language; it was referred to as both) that compiled into a [[byte code]] able to run on a standardized [[virtual machine]] called the [[Z-machine]]. As the games were text based and used variants of the same Z-machine interpreter, the interpreter only had to be ported to a [[computer]] once, rather than once each game. Each game file included a sophisticated [[parser]] which allowed the user to type complex instructions to the game. Unlike earlier works of interactive fiction which only understood commands of the form 'verb noun', Infocom's parser could understand a wider variety of sentences. For instance one might type "open the large door, then go west", or "go to the hall". With the Z-machine, Infocom was able to release most of their games for most popular [[home computer]]s of the time simultaneously, including [[Apple II]], [[Atari 8-bit computers]], [[IBM PC compatible]]s, [[Amstrad CPC]]/[[Amstrad PCW|PCW]] (one disc worked on both machines), [[Commodore 64]], [[Commodore Plus/4]], [[Commodore 128]], [[Kaypro]] [[CP/M]], [[TI-99/4A]], [[Macintosh]], [[Atari ST]], [[Amiga]], and [[TRS-80]].

During the 1990s Interactive fiction was mainly written with C-like languages, such as [[TADS]] 2 and [[Inform]] 6. A number of systems for writing interactive fiction now exist. The most popular remain [[Inform]], [[TADS]], or [[ADRIFT]], but they diverged in their approach to IF-writing during the 2000s, giving today's IF writers an objective choice. By 2006 [[IFComp]], most games were written for Inform, with a strong minority of games for TADS and ADRIFT, followed by a small number of games for other systems.<ref name="ifcomp">{{cite web| url = http://www.ifcomp.org/comp06/games.php| title = Games of the 12th Annual Interactive Fiction Competition| access-date = 17 December 2006| year = 2006|url-status=live| archive-url = https://web.archive.org/web/20070103031237/http://www.ifcomp.org/comp06/games.php| archive-date = 3 January 2007| df = dmy-all}}</ref>

While familiarity with a programming language leads many new authors to attempt to produce their own complete IF application, most established IF authors recommend use of a specialised IF language, arguing that such systems allow authors to avoid the technicalities of producing a full featured parser, while allowing broad community support. The choice of [[authoring system]] usually depends on the author's desired balance of ease of use versus power, and the portability of the final product.<ref name=brasslantern>{{cite web| url = http://brasslantern.org/writers/howto/chooselang.html| title = Choosing a Text Adventure Language| access-date = 17 December 2006| last = Granade| first = Stephen|url-status=live| archive-url = https://web.archive.org/web/20061205043134/http://brasslantern.org/writers/howto/chooselang.html| archive-date = 5 December 2006| df = dmy-all}}</ref>

Other development systems include:
* David Malmberg's [[Adventure Game Toolkit]] (AGT)
* [[Incentive Software]]'s [[Graphic Adventure Creator]] (GAC)
*[[Inkle (company)|Inkle]]'s [[Inkle (company)#Inklewriter|inklewriter]]
* [[Professional Adventure Writer]]
* [[Gilsoft]]'s [[The Quill Adventure System|The Quill]]
* [[Twine (software)|Twine]]

===Interpreters and virtual machines===
[[Interpreter (computing)|Interpreters]] are the software used to play the works of interactive fiction created with a development system. Since they need to interact with the player, the "story files" created by development systems are programs in their own right. Rather than running directly on any one computer, they are programs run by Interpreters, or virtual machines, which are designed specially for IF. They may be part of the development system, or can be compiled together with the work of fiction as a standalone [[executable file]].

The Z-machine was designed by the founders of [[Infocom]], in 1979. They were influenced by the then-new idea of a [[P-machine|virtual Pascal computer]], but replaced P with Z for Zork, the celebrated adventure game of 1977–79. The Z-machine evolved during the 1980s but over 30 years later, it remains in use essentially unchanged. Glulx was designed by Andrew Plotkin in the late 1990s as a new-generation IF virtual machine. It overcomes the technical constraint on the Z-machine by being a 32-bit rather than 16-bit processor. [[Frotz]] is a modern Z-machine interpreter originally written in [[C (programming language)]] by Stefan Jokisch in 1995 for [[DOS]]. Over time it was ported to other platforms, such as Unix, RISC OS, Mac OS and most recently iOS. Modern Glulx interpreters are based on "Glulxe", by Andrew Plotkin, and "Git", by Iain Merrick. Other interpreters include Zoom for Mac OS X, or for Unix or Linux, maintained by Andrew Hunter, and Spatterlight for Mac OS X, maintained by Tor Andersson.

===Distribution===
In addition to commercial distribution venues and individual websites, many works of free interactive fiction are distributed through community websites. These include the Interactive Fiction Database (IFDb), The Interactive Fiction Reviews Organization (IFRO), a game catalog and recommendation engine, and the Interactive Fiction Archive.

Works may be distributed for playing with in a separate interpreter. In which case they are often made available in the [[Blorb]] [[package format]] that many interpreters support. A filename ending .zblorb is a story file intended for a Z-machine in a Blorb wrapper, while a filename ending .gblorb is a story file intended for a Glulx in a Blorb wrapper. It is not common but IF files are sometimes also seen without a Blorb wrapping, though this usually means cover art, help files, and so forth are missing, like a book with the covers torn off. Z-machine story files usually have names ending .z5 or .z8, the number being a version number, and Glulx story files usually end .ulx.

Alternatively, works may be distributed for playing in a [[web browser]]. For example, the 'Parchment' project is for web browser-based IF Interpreter, for both Z-machine and Glulx files.

Some software such as [[Twine (software)|Twine]] publishes directly to [[HTML]], the standard language used to create [[web pages]], reducing the requirement for an Interpreter or virtual machine.