Editing Colossal Cave Adventure (section)

===Crowther's original version===
[[File:Will Crowther Fall 2012.jpg|right|thumb|William Crowther in 2012|alt=William Crowther]]
[[File:ASR-33 at CHM.agr.jpg|right|thumb|[[Teleprinter]] [[computer terminal]]|alt=ASR-33 Teleprinter]]
''Colossal Cave Adventure'' was originally created by [[William Crowther (programmer)|William Crowther]] in 1975 and 1976. Crowther and his ex-wife [[Patricia Crowther (caver)|Patricia]] were both programmers and [[caving|cavers]] and had extensively explored [[Mammoth Cave National Park|Mammoth Cave]] in [[Kentucky]], the longest cave system in the world, in the early 1970s as part of the [[Cave Research Foundation]]. In 1972, Patricia led the expedition that found a connection between Mammoth Cave and the larger Flint Ridge Cave System. In addition to caving, the pair produced [[vector (mathematics and physics)|vector]] map surveys of the cave: they transcribed the survey data of the cave from "muddy little books" into a [[teleprinter]] terminal in their house, which could send and print messages from programs running on the central computer and was connected to a [[PDP-1]] [[mainframe computer]] at [[Raytheon BBN|Bolt, Beranek and Newman]] (BBN) where William Crowther worked. This data was then fed into a program developed by the pair that generated [[plot (graphics)|plotting]] commands onto [[punched tape]], which were then fed into a [[Honeywell 316]] [[minicomputer]] attached to a [[Calcomp plotter|Calcomp drum plotter]] at BBN to print paper maps. These maps were some of the earliest computer-drawn maps of caves.<ref name="BroadBand"/>

In 1975, after he and Patricia divorced, William Crowther stopped caving with the Cave Research Foundation. Driven by what he later described as an increase in spare time combined with missing his two daughters, he began working on a text-based game in [[Fortran]] on BBN's [[PDP-10]] mainframe, interfacing through a teletype printer, that they could play.<ref name="DH2007"/><ref name="Lessard2013"/><ref name="Peterson187188"/> He combined his memories and maps of the Mammoth Cave system, particularly a 1975 map of the Bedquilt area of the caves, including [[Colossal Cavern]], with elements of the ''[[Dungeons & Dragons]]'' campaigns that he played with friends to design a game around exploring a cave for treasure.<ref name="DH2007"/><ref name="Peterson187188"/> Crowther wanted the game to be accessible and not intimidating to non-technical players such as his children, and so developed a [[natural language processing|natural language input]] system to control the game so that it would be "a thing that gave you the illusion anyway that you'd typed in English commands and it did what you said".<ref name="Montfort9192"/> Crowther later commented that this approach allowed the game to appeal to both non-programmers and programmers alike, as in the latter case, it gave programmers a challenge of how to make "an obstinate system" perform in a manner they wanted it to.<ref name="Montfort9192"/> This approach was also developed to allow the game to be played on a teletype printer, rather than rely on user interface elements used in programs designed for monitors.<ref name="Lessard2013"/>

The initial version of the game was about 700 lines of code, plus another 700 lines of data such as descriptions for 66 rooms, navigational messages, 193 vocabulary words, and miscellaneous messages.<ref name="DH2007"/><ref name="OriginalSourceCode"/> Once the game was complete, in early 1976, Crowther showed it off to his co-workers at BBN for feedback, and then considered his work on the game finished, leaving the compiled game on the mainframe before taking a month off for vacation. According to one of Crowther's then-coworkers in 2007, "once it was working, Will wasn't very interested in perfecting or expanding it." Crowther's work at BBN was in developing [[ARPANET]], one of the first networks of computers and a precursor to the Internet, and the PDP-10 mainframe was part of that network. During his vacation, others found the game and it was distributed widely across the network to computers at other companies and universities, which surprised Crowther on his return. The game did not have an explicit title in it, simply stating "WELCOME TO ADVENTURE!!" as a part of the opening message and having a file name of ADVENT; it was referred to as both ''Adventure'' and ''Colossal Cave Adventure'', with the latter becoming the more common name over time.<ref name="DH2007"/> Most [[computer terminal]]s at the time did not have [[computer monitor|monitors]], and players would instead play the game over teleprinters connected to the mainframe.<ref name="teleprinter"/>