View source for DOOM

:''See [[Dōm]] For the Anglo-Saxon concept. For other uses, see [[Doom (disambiguation)]].''

|image = [[Image:Doom-boxart.jpg|center|250px|The Doom title artwork, painted by Don Ivan Punchatz, depicts the lone hero, a space marine, fighting demonic creatures.]]

'''''Doom''''' (or '''''DOOM'''''){{fn|a}} is a [[1993]] [[computer game]] by [[id Software]] that is among the landmark titles in the [[first-person shooter]] genre. It is widely recognized for its pioneer use of immersive [[3D computer graphics|3D graphics]], [[multiplayer|networked multiplayer gaming]], and the support for players to create custom expansions ([[Doom WAD|WAD]]s). Distributed as [[shareware]], ''Doom'' was downloaded by an estimated 10 million people within two years, popularizing the mode of gameplay and spawning a gaming [[subculture]]; as a sign of its impact on the industry, games from the mid-[[1990s]] boom of first-person shooters are often known simply as "[[Doom clone|''Doom'' clones]]". Its graphic and interactive [[violence]]{{ref|ESRB}} has also made ''Doom'' the subject of much [[video game controversy|controversy]] reaching outside the gaming world.

The ''Doom'' franchise was continued with ''[[Doom II|Doom II: Hell on Earth]]'' ([[1994]]) and numerous [[expansion pack]]s, including ''[[Versions and ports of Doom|The Ultimate Doom]]'' ([[1995]]), ''[[Master Levels for Doom II]]'' ([[1995]]), and ''[[Final Doom]]'' ([[1996]]). Originally released for [[personal computer|PC]]/[[DOS]], these games have later been [[porting|ported]] to many other platforms, including nine different [[game console]]s. The series lost mainstream appeal as the technology of the [[Doom engine|''Doom'' game engine]] was surpassed in the mid-1990s, although fans have continued making WADs, [[speedrunning]], and modifying the [[source code]] which was released in [[1997]]. The franchise again received popular attention in [[2004]] with the release of ''[[Doom 3]]'', a retelling of the original game using new technology, and an associated [[2005]] [[Doom (film)|''Doom'' motion picture]].

==Game features==

===Story===
''Doom'' has a [[science-fiction]]-[[horror (genre)|horror]]-theme, and a simple [[plot]]. The background is only given in the game's manual, and the in-game story is mainly advanced with short messages displayed between the game's episodes.

The player takes the role of a nameless [[space marine]], "one of Earth's toughest, hardened in combat and trained for action", who has been deported to [[Mars]] for assaulting a senior officer when ordered to kill unarmed civilians. He is forced to work for the [[Union Aerospace Corporation]] (UAC), a military-industrial conglomerate that is performing secret experiments with [[teleportation]] between the moons of Mars, [[Phobos (moon)|Phobos]] and [[Deimos (moon)|Deimos]]. Suddenly, something goes wrong and creatures from [[Hell]] come out of the teleportation gates. A defensive response from base security fails to halt the invasion, and the bases quickly get overrun by [[demon]]s, all personnel getting killed or turned into [[zombie]]s. At the same time, Deimos vanishes entirely. A UAC team from Mars is sent to Phobos to investigate the incident, but soon [[radio]] contact ceases and only one human is left alive &mdash; the player, whose task is to make it out alive.{{ref|story}}

[[Image:Doom_ingame_1.png|thumb|240px|''Episode I: Knee-Deep in the Dead'' takes place in the [[military base]] on [[Phobos (moon)|Phobos]].  In this image the main character is currently using the [[chainsaw]], a powerful [[mêlée]]-only weapon.  Pools of [[toxic waste]] are visible on both sides, and a [[zombie|zombified]] human approaches.]]
[[Image:Doom ingame 2.png|right|thumb|240px|''Episode III: Inferno'' is set in [[Hell]]. The main character has just fired the [[shotgun]] at a group of [[Imp]]s and is cycling it. He is badly injured and has only seven shells left.]]

{{spoiler}}

In order to beat the game, the player must fight through three episodes containing nine [[level (computer and video games)|level]]s each (see [[Episodes and levels of Doom|Episodes and levels of ''Doom'']]). ''Knee-Deep in the Dead'', the first episode and the only one in the [[shareware]] version, is set in the high-tech military bases on Phobos. It ends with the player fighting the [[Doom enemies#Baron of Hell|Barons of Hell]] and afterwards entering the teleporter leading to Deimos, there getting overwhelmed by monsters and seemingly killed. In the second episode, ''Shores of Hell'', the player journeys through the Deimos installation, whose areas are interwoven with beastly architecture. After encountering the [[Doom enemies#Cyberdemon|Cyberdemon]], the truth about the vanished moon is discovered: it is floating above Hell. The player climbs down to the surface, and the final episode, ''Inferno'', begins. After destroying the final [[boss (video games)|boss]], the [[Doom enemies#Spider Mastermind|Spider Mastermind]], a hidden doorway opens for the hero who has "proven too tough for Hell to contain", leading back home to Earth. The expansion pack ''[[Ultimate Doom]]'' adds a fourth episode, ''Thy Flesh Consumed'', chronicling the marine's return to Earth.

===Gameplay===
''Main article: [[Gameplay of Doom]]''

Being a [[first-person shooter]], ''Doom'' is experienced through the eyes of the main character. The objective of each level is simply to locate the exit room that leads to the next area (usually labeled with an inviting red EXIT sign), while surviving all hazards on the way. Among the obstacles are monsters, pits of [[radioactive waste|radioactive slime]], ceilings that come down and [[crushing|crush]] the player, and locked doors for which a [[keycard]] or remote switch need to be located. The levels are sometimes labyrinthine (the [[automap]] is a crucial aid in navigating them), and feature plenty of hidden secret areas that hold [[power-up]]s as a reward for players who explore.

''Doom'' is notable for the [[weapon]]s arsenal available to the player, which became prototypical for first-person shooters. The player starts armed only with a [[pistol]], and [[brass knuckles|brass-knuckled]] [[fist]]s in case the [[ammunition]] runs out, but larger weapons can be picked up: these are a [[chainsaw]], a [[shotgun]], a [[chaingun]], a [[rocket launcher]], a [[plasma rifle]], and finally the immensely powerful [[BFG 9000]]. There is a wide array of power-ups, such as a [[backpack]] that increases the player's ammunition-carrying capacity, [[armor]], [[first aid kit]]s to restore health, and blue demonic orbs that boost the player's health percentage beyond 100%, up to a maximum of 200%.

The enemy monsters in ''Doom'' make up the central gameplay element. The player faces them in large numbers, on the higher of the game's five [[difficulty level]]s often encountering a dozen or more in the same room. There are 10 types of monsters (''[[Doom II]]'' doubles this figure), including possessed humans as well as [[demon]]s of different strength, ranging from weak but ubiquitous [[imp]]s and red, floating [[cacodemon]]s, to the [[boss (video games)|bosses]] which survive multiple strikes even from the player's strongest weapons. The monsters have very simple behavior, consisting of either walking toward the player or attacking by throwing fireballs, biting, and scratching (though they can also [[monster infighting|fight each other]]).

Aside from the [[single-player]] game mode, ''Doom'' features two [[multiplayer]] modes playable over a [[computer network|network]]: "co-operative", in which two to four players team up against the legions of Hell, and "[[deathmatch]]", in which two to four players fight each other.
{{multi-video start}}
{{multi-video item|filename=Doom single-player E3M6.ogg|title=''Doom'' single-player gameplay demonstration|description=Video of a single-player game, in the level ''E3M6: Mount Erebus''.|format=[[Theora]]}}
{{multi-video end}}

==Development==
''Main article: [[Making of Doom]]''

[[Image:Adrian Carmack cropped.jpg|thumb|240px|Some of the ''Doom'' monsters were digitized from sculptures. Here, [[Adrian Carmack]] creates the [[Doom enemies#Baron of Hell|Baron of Hell]] in clay.]]

The development of ''Doom'' started in [[1992]] with [[John Carmack]] creating the new [[game engine]], the [[Doom engine|''Doom'' engine]], while the rest of the team finished ''[[Spear of Destiny (computer game)|Spear of Destiny]]''. When the [[game design]] phase began in late 1992, the main thematic influences were the [[science fiction]] [[action movie]] ''[[Aliens (1986 film)|Aliens]]'' and the [[horror movie]] ''[[Evil Dead II]]''. The title of the game was picked by Carmack:
:''There is a scene in "[[The Color of Money]]" where [[Tom Cruise|Tom Cruse]] ''[sic]'' shows up at a pool hall with a custom pool cue in a case. "What do you have in there?" asks someone. "Doom." replied Cruse with a cocky grin. That, and the resulting carnage, was how I viewed us springing the game on the industry.'' {{ref|DWCarmack}}

Designer [[Tom Hall]] wrote an elaborate [[design document]] called the ''Doom Bible'', according to which the game would feature a detailed storyline, multiple player characters, and a number of interactive features.{{ref|bible}} However, many of his ideas were discarded during development in favor of simpler design primarily advocated by Carmack, resulting in Hall in the end being forced to resign due to not contributing effectively in the direction the rest of the team was going. Most of the [[level design]] that ended up in the final game is that of [[John Romero]] and [[Sandy Petersen]]. The graphics, by [[Adrian Carmack]], [[Kevin Cloud]] and [[Gregor Punchatz]], were created in various ways: although much was drawn or painted, several of the monsters were digitized from sculptures in [[clay]] or [[latex]], and some of the weapons are toy guns from [[Toys "R" Us]]. A [[heavy metal music|heavy metal]]-[[ambient music|ambient]] soundtrack was supplied by [[Bobby Prince]]. {{ref|MastersOfDoom}}

===Engine technology===
''Main article: [[Doom engine]]''

''Doom''<nowiki>'</nowiki>s primary distinguishing feature at the time of its release was its realistic [[3D computer graphics|3D graphics]], then unparalleled by other [[real-time computing|real-time]]-rendered games running on consumer-level hardware. The advance from id Software's previous game ''[[Wolfenstein 3D]]'' was enabled by several new features in the ''Doom'' engine:

[[Image:Doom darkness.png|thumb|240px|''Doom'' relies heavily on contrasts of lighting in building its atmosphere.]]

* Height differences (all rooms in ''Wolfenstein 3D'' are at the same altitude);
* Non-[[perpendicular]] walls (all walls in ''Wolfenstein 3D'' run along a rectangular grid);
* Full [[texture mapping]] of all surfaces (in ''Wolfenstein 3D'', floors and ceilings are not texture mapped); and,
* Varying light levels (all areas in ''Wolfenstein 3D'' are fully lit at the same brightness). While contributing to the game's visual authenticity by allowing effects such as highlights and shadows, this perhaps most importantly added to the game's atmosphere and even gameplay; the use of darkness as a means of frightening or confusing the player was an unseen element in games.

In contrast to the static levels of ''Wolfenstein 3D'', those in ''Doom'' are highly interactive: platforms can lower and rise, floors can raise sequentially to form [[staircase]]s, and bridges can raise and lower. The life-like feeling of the environment was enhanced further by the [[stereo sound]] system, which made it possible to roughly tell the direction and distance of a sound's origin. The player is kept on guard by the grunts and gnarls of monsters, and receives occasional clues to finding secret areas in the form of sounds of hidden doors opening remotely. Monsters can also become aware of the player's presence by hearing distant gunshots.

Carmack had to make use of several tricks for these features to run smoothly on 1993's home computers. Most significantly, ''Doom'' levels are not truly three-dimensional; they are internally represented on a [[plane (mathematics)|plane]], with height differences added separately (a similar trick is still used by many games to create huge outdoor environments). This leads to several limitations: it is, for example, not possible for a ''Doom'' level to have one room over another. This two-dimensional representation does, however, have the benefit that rendering can be done very quickly, using a [[Binary space partitioning|binary space partitioning]] method. Another benefit was the clearness of the automap because it could be displayed with 2D vectors without the risk of overlapping.

Another important feature of the ''Doom'' engine is a modular approach that allows the game content to be replaced by loading custom [[Doom WAD|WAD files]]. ''Wolfenstein 3D'' was not designed to be expansible, but fans had nevertheless figured out how to create their own levels for it, and ''Doom'' was designed to take the phenomenon further. The ability to create custom scenarios contributed significantly to the game's popularity (see the section on [[#WADs|WADs]] below).

==Release and later history==

===Initial popularity===
The development of ''Doom'' was surrounded by much anticipation. The large number of posts in Internet [[newsgroup]]s about ''Doom'' led to the [[SPISPOPD]] joke, to which a nod was given in the game in the form of a [[cheat code]]. In addition to news, rumors, and [[screenshot]]s, unauthorized leaked [[alpha version]]s also circulated online. (Many years later these alpha versions were sanctioned by id Software because of historical interest; they reveal how the game progressed from its early design stages.) The first public version of ''Doom'' was uploaded to an [[FTP]] run at the [[University of Wisconsin]] on [[December 10]], [[1993]].

Released as [[shareware]], people were encouraged to distribute ''Doom'' further, and did so: in [[1995]], ''Doom'' was estimated to have been installed on more than 10 million computers. Although most users did not purchase the registered version, over one million copies have been sold, and the popularity helped the sales of later games in the ''Doom'' series which were not released as shareware. In 1995, ''[[The Ultimate Doom]]'' (version 1.9, including episode IV) was released, making this the first time that ''Doom'' was sold commercially in stores. 

[[Image:Billdoom.png|thumb|240px|Recognizing the game's popularity, [[Bill Gates]] made a presentation to promote [[Windows 95]] while digitally superimposed into ''Doom'' to blast zombies.]]

In a press release dated [[January 1]], [[1993]], id Software had written that they expected ''Doom'' to be "the number one cause of decreased productivity in businesses around the world". This prediction came true at least in part: ''Doom'' became a major problem at workplaces, both occupying the time of employees and clogging [[computer network]]s with traffic caused by deathmatches. [[Intel]], [[Lotus Development]] and [[Carnegie Mellon University]] are among many organizations reported to form policies specifically disallowing ''Doom''-playing during work hours. At the [[Microsoft]] campus, ''Doom'' was by one account{{ref_label|MastersOfDoom|5a|a}} equal to a "religious phenomenon".

In late 1995, ''Doom'' was estimated to be installed on more computers worldwide than Microsoft's new operating system [[Windows 95]], despite million-dollar advertising campaigns for the latter. The game's popularity prompted [[Bill Gates]] to briefly consider buying id Software, and led Microsoft to develop a Windows 95 port of ''Doom'' to promote the operating system as a gaming platform. One such presentation to promote Windows 95 had Bill Gates digitally superimposed into the game. {{ref|BillGates}}

''Doom'' was also widely praised in the gaming press. In [[1994]], it was awarded [[Game of the Year]] by both [[PC Gamer]] and [[Computer Gaming World]]. It also received the Award for Technical Excellence from [[PC Magazine]], and the Best Action Adventure Game award by the [[Academy of Interactive Arts & Sciences]].

In addition to the thrilling nature of the single-player game, the [[deathmatch]] mode was an important factor in the game's popularity. ''Doom'' was not the first first-person shooter with a deathmatch mode&mdash;''[[MIDI Maze]]'' on the [[Atari ST]] had one in [[1987]], using the [[MIDI]] ports built into the ST to network up to four machines together. However, ''Doom'' was the first game to allow deathmatching over [[ethernet]], and the combination of violence and gore with fighting friends made deathmatching in ''Doom'' particularly attractive. Two player deathmatch was also possible over a phone line by using a [[modem]]. Due to its widespread distribution, ''Doom'' hence became the game that introduced deathmatching to a large audience (and was also the first game to use the term "deathmatch").

===WADs===
''Main article: [[Doom WAD]]s''

[[Image:Ghostbusters Doom.png|thumb|240px|''[[Ghostbusters]]'' is one of many movies that have been made into ''Doom'' WADs.]]

The ability to create custom levels and otherwise modify the game, in the form of custom [[WAD file]]s, turned out to be a particularly popular aspect of ''Doom''. Gaining the first large [[mod (computer gaming)|mod]]-making community, ''Doom'' affected the culture surrounding first-person shooters, and also the industry. Several to-be professional [[game designer]]s started their careers making ''Doom'' WADs as a hobby, among them [[Tim Willits]], who later became the lead designer at id Software.

The first [[level editor]]s appeared in early [[1994]], and additional tools have been created that allow most aspects of the game to be edited. Although the majority of WADs contain one or several custom levels mostly in the style of the original game, others implement new monsters and other resources, and heavily alter the gameplay; several popular movies, television series and other brands from popular culture have been turned into ''Doom'' WADs by fans (without authorization), including ''[[Aliens (1986 film)|Aliens]]'', ''[[Star Wars]]'', ''[[The X-files]]'', ''[[The Simpsons]]'' and ''[[Batman]]''.

Some addon files were also made which changed the sounds made by the various characters and weapons. Notable ones were samples from [[beavis and butthead]] and the famous orgasm scene from ''[[When Harry Met Sally...]]''.

Around [[1994]] and [[1995]], WADs were primarily distributed online over [[bulletin board system]]s or sold in collections on [[compact disc]]s in computer shops, sometimes bundled with editing guide books. [[FTP]] servers became the primary method in later years. A few WADs have been released commercially, including the ''[[Master Levels for Doom II]]'', which was released in [[1995]] along with ''Maximum Doom'', a CD containing 1,830 WADs that had been downloaded from the Internet. Several thousands of WADs have been created in total: the ''idgames'' FTP archive contains over 13,000 files{{ref|idgamesCount}}, and this does not represent the complete output of ''Doom'' fans.

Third party programs were also written to handle the loading of various WADs, since the game is a [[DOS]] game and all commands had to be entered on the [[command line]] to run. A typical launcher would allow the player to select which files to load from a menu, making it much easier to start.

===Clones and related products===
''Main articles: [[Doom clone]]s, [[Versions and ports of Doom]], [[Doom spin-offs and homages]]''

[[Image:Doom clone vs first person shooter.png|thumb|240px|The phrase "[[Doom clone|''Doom'' clone]]" was initially popular to describe the style of gameplay in ''Doom''-like games, but after [[1996]] was gradually replaced by the more generic "[[first person shooter]]".]]

The popularity of ''Doom'' led to the development of a sequel, ''[[Doom II: Hell on Earth]]'' ([[1994]]), as well as expansion packs and alternate versions based on the same game engine, including ''[[The Ultimate Doom]]'' ([[1995]]), ''[[Final Doom]]'' ([[1996]]), and ''[[Doom 64]]'' ([[1997]]). ''Doom'' became a [[killer application]] that all capable [[game console|console]]s and [[operating system]]s were expected to have, and versions of ''Doom'' have subsequently been released for the following systems: [[DOS]], [[Microsoft Windows]], [[QNX]], [[Irix]], [[NEXTSTEP]], [[Linux]], [[Apple Macintosh]], [[Super Nintendo Entertainment System|Super NES]], [[Sega 32X]], Sony [[PlayStation]], [[Game Boy Advance]], [[RiscOS]], [[Atari Jaguar]], [[Sega Saturn]], [[Nintendo 64]], the [[Tapwave Zodiac]] and [[3DO Interactive Multiplayer|3DO]]. The total number of copies of ''Doom'' games sold is unknown, but may be well over 4 million{{ref|sales}}; ''Doom II'' alone has sold for over $100 million.

The game engine was licensed to several other companies as well, who released their own games based on it, including ''[[Heretic (computer game)|Heretic]]'', ''[[HeXen]]'', ''[[Strife]]'' and ''[[HacX]]''. There is also a ''Doom''-based game released by a breakfast [[cereal]] maker as a product tie-in called ''[[Chex Quest]]'', and the [[United States Marine Corps]] released ''[[Marine Doom]]'', designed to "teach teamwork, coordination and decision-making".

Dozens of new first-person shooter titles appeared following ''Doom''<nowiki>'</nowiki>s release, and they were often referred to as "[[Doom clone|''Doom'' clones]]" rather than "first-person shooters". Some of these were certainly "clones"&mdash;hastily assembled and quickly forgotten about&mdash;others explored new grounds of the genre and were highly acclaimed. ''Doom''<nowiki>'</nowiki>s principal rivals were [[Apogee Software|Apogee]]'s ''[[Rise of the Triad]]'' and [[Origin Systems]]' ''[[System Shock]]''. The popularity of ''[[Star Wars]]''-themed WADs is rumored to have been the factor that prompted [[LucasArts]] to create their first-person shooter ''[[Dark Forces]]''. {{ref|GamespyClones}}

When, three years later, [[3D Realms]] released ''[[Duke Nukem 3D]]'', a tongue-in-cheek science fiction shooter based on [[Ken Silverman]]'s technologically similar [[Build engine|''Build'' engine]], id Software had nearly finished ''[[Quake]]'', its next-generation game, which mirrored ''Doom''<nowiki>'</nowiki>s success for the remainder of the [[1990s]] and significantly reduced interest in its predecessor. The franchise remained in that state until [[2000]], when ''[[Doom 3]]'' was announced. A retelling of the original ''Doom'' using entirely new graphics technology,  ''Doom 3'' was [[hype]]d to provide as large a leap in realism and interactivity as the original ''Doom'', but received mixed reactions when released in [[2004]].

''Doom'' has appeared in several forms in addition to games, including a [[Doom comic book|comic book]], four novels by [[Dafydd Ab Hugh]] and [[Brad Linaweaver]] (loosely based on events and locations in the games), and [[Doom (movie)|a film]] starring [[Karl Urban]] and [[The Rock (entertainer)|The Rock]] released in [[2005]]. The game's development and impact on popular culture is also the subject of the book ''[[Masters of Doom]]'' by [[David Kushner]].

===Controversy===
[[Image:Doom gibs.png|thumb|240px|The [[Shoulder-launched missile weapon|rocket launcher]] can be used to explode enemies into piles of [[gibs]]; the graphic violence made ''Doom'' highly controversial.]]

''Doom'' was and remains notorious for its high levels of [[violence]], [[gore]], and [[Satanism|Satanic]] imagery, which have generated much controversy from a broad range of groups. It has been criticized numerous times by [[Christianity|Christian]] organizations for its diabolic undertones and was dubbed a "mass murder simulator" by critic and [[Killology Research Group]] founder [[Dave Grossman (author)|Lt. Col. David Grossman]].{{ref|Grossman}} ''Doom'' prompted fears that the then-emerging [[virtual reality]] technology could be used to simulate extremely realistic killing, and in [[1994]] led to unsuccessful attempts by [[Washington]] [[State Senator|state senator]] [[Phil Talmadge]] to introduce compulsory licensing of VR use.

The game again sparked controversy throughout a period of [[school massacre|school shooting]]s in the [[United States]] when it was found that [[Eric Harris and Dylan Klebold]], who committed the [[Columbine High School massacre]] in [[1999]], were avid players of the game. While planning for the massacre, Harris said that the killing would be "like fucking ''Doom''" and that his shotgun was "straight out of" the game{{ref|Columbine}}. A rumor spread afterwards that Harris had designed ''Doom'' levels that looked like the halls of the high school, populated with representations of Harris's classmates and teachers, and that Harris practiced for Columbine by playing these levels over and over. However, although Harris did design ''Doom'' levels, they were not simulations of Columbine (see [[Harris levels]]).

===Continued legacy===
''Doom'' is widely regarded as one of the [[Computer and video games that have been considered the greatest ever|most important titles]] in gaming history. It was voted the "#1 game of all time" in a poll among over 100 game developers and journalists conducted by [[GameSpy]] in [[July]] [[2001]]{{ref|no1}}, and [[PC Gamer]] proclaimed ''Doom'' the most influential game of all time in its ten-year anniversary issue in [[April]] [[2004]]. However, several game journalists have also contrasted the relatively simplistic gameplay in ''Doom'' unfavorably with more story-oriented first-person shooters such as ''[[Half-Life]]''.

Although the popularity of the ''Doom'' games dropped with the release of ''[[Quake]]'' ([[1996]]) and afterwards, the games have retained a strong fan base that continues playing competitively and creating [[Doom WAD|WADs]] (the ''idgames'' FTP archive receives a few to a dozen new WADs each week [[as of 2005]]), and ''Doom''-related news is still tracked at multiple websites such as [[Doomworld]]. Interest in ''Doom'' was renewed in [[1997]], when the [[source code]] for the ''Doom'' engine was released (it was also placed under the [[GNU General Public License]] in [[1999]]). Fans then began [[porting]] the game to various operating systems, even to previously unsupported platforms such as the [[Dreamcast]], [[PlayStation Portable|PSP]] and the [[iPod]], and adding new features such as [[OpenGL]] rendering and [[scripting]], which allows WADs to alter the gameplay more radically. There are well over 50 different [[Doom source port|''Doom'' source ports]], some of which remain under active development.

Devoted players have spent years creating [[Doom speedrunning|speedruns for ''Doom'']], competing for the quickest completion times and sharing knowledge about routes through the levels and how to exploit [[computer bug|bug]]s in the ''Doom'' engine for shortcuts. Achievements include the completion of both ''Doom'' and ''Doom II'' on the ''Ultra-Violence'' difficulty setting in less than 30 minutes each. In addition, a few players have also managed to complete ''Doom II'' in a single run on the ''Nightmare!'' difficulty setting, on which monsters are twice as fast and respawn some time after they have been killed (level designer [[John Romero]] characterized the idea of such a run as "[just having to be] impossible"{{ref|Nightmare}}). Movies of most of these runs are available from the [[COMPET-N]] website.

==References==
# {{note|ESRB}} {{Web reference |author=Entertainment Software Rating Board |title=Game ratings |url=http://www.esrb.org/search_results.asp?key=doom&x=0&y=0&type=game |date=December 4 |year=2004}}
# {{note|story}} {{Web reference |author=id Software |title=The ''Doom'' instruction manual (unofficial transcript) |publishyear=1993 |url=http://oregonstate.edu/~lloydo/doomstory.txt |date=November 15 |year=2005}}
# {{note|DWCarmack}} {{Web reference |author=Doomworld |title=Interview with John Carmack |url=http://doomworld.com/interviews/int7.shtml |date=November 15 |year=2005}}
# {{note|bible}} {{Web reference |author=Hall, Tom |title=The Doom Bible |publishyear=1992 |publisher=Doomworld (1998) |url=http://5years.doomworld.com/doombible/ |date=November 15 |year=2005}}
# {{note|MastersOfDoom}}{{note_label|MastersOfDoom|6|a}} {{Book reference |Author=Kushner, David |Title=[[Masters of Doom: How Two Guys Created an Empire and Transformed Pop Culture]] |Publisher=Random House Publishing Group |Year=2003 |ID=ISBN 0-3755-0524-5}}
# {{note|BillGates}} {{Web reference |author=Lombardo, Mike |publisher=Reel Splatter |title=Bonus movie: Bill Gates "DOOM" video |url=http://www.reelsplatter.com/downloads.htm |date=November 15 |year=2005}}
# {{note|idgamesCount}} {{Web reference |author=Doomworld |title=/idgames database |url=http://www.doomworld.com/idgames/ |date=September 3 |year=2005}}
# {{note|sales}} {{Web reference |author=Doom Wiki |title=Sales |url=http://doom.wikicities.com/wiki/Sales |date=November 15 |year=2005 |publishyear=2005}}
# {{note|GamespyClones}} {{Web reference |author=Turner, Benjamin & Bowen, Kevin |title=Bringin' in the DOOM Clones |url=http://archive.gamespy.com/articles/december03/doom/clones/index2.shtml |publisher=GameSpy |publishyear=2003 |date=November 15 |year=2005}}
# {{note|Grossman}} {{Web reference |author=Irvine, Reed & Kincaid, Cliff |title=Video Games Can Kill |url=http://www.aim.org/media_monitor/A3327_0_2_0_C/ |publisher=Accuracy In Media |publishyear=1999 |date=November 15 |year=2005}}
# {{note|Columbine}} {{Web reference |author=4-20: a Columbine site |title=Basement Tapes: quotes and transcripts from Eric Harris and Dylan Klebold's video tapes |url=http://columbine.free2host.net/quotes.html |date=November 15 |year=2005}}
# {{note|no1}} {{Web reference |author=GameSpy |title=GameSpy's Top 50 Games of All Time |url=http://archive.gamespy.com/articles/july01/top50index/ |publishyear=2001 |publisher=GameSpy |date=November 15 |year=2005}}
# {{note|Nightmare}} {{Web reference |author=Hegyi, Adam |title=Player profile for Thomas "Panter" Pilger |publishyear=1992 |url=http://www.doom2.net/~compet-n/index.cgi?action=players&page=panter |date=November 15 |year=2005}}
* {{Web reference |author=Leukart, Hank |title=The "Official" Doom FAQ |publishyear=1994 |url=http://www.gamers.org/docs/FAQ/doomfaq/ |date=November 15 |year=2005}}
* {{Web reference |author=Romero, John |title=1993: Doom |work=Planet Rome.ro |url=http://rome.ro/games_doom.htm |date=November 15 |year=2005}}

==Notes==
*{{fnb|a}} The variations ''Doom'' and ''DOOM'' have both been used in official contexts. The variation ''DooM'', stylized after the game's logo, is also occasionally encountered, but has fallen out of use almost completely in recent years.

==External links==
{{wikiquote}}
{{wikibooks}}
* Official websites
** [http://www.idsoftware.com/games/doom/ ''Doom'' at id Software's official website]
** [http://www.activision.com/en_US/brand/4689f00d-2019-4646-b3ee-f262531c33d6.html ''Doom'' at Activision's official website]

* Unofficial portal sites with ''Doom''-related news, forums, information resources, and downloads
** [http://www.doomworld.com/ Doomworld.com] - [[Doomworld]]
** [http://www.planetdoom.com/ PlanetDoom.com]
** [http://www.newdoom.com/ NewDoom.com]

* Information resources
** [http://doom.wikicities.com/wiki/Entryway The Doom Wiki] at [[Wikicities]] - includes encyclopedic articles, trivia, strategy guides, and editing information
** [http://www.classicdoom.com/ ClassicDoom.com] - focuses on walkthroughs and comparisons of ''Doom'' versions
** [http://www.doomworld.com/pageofdoom The Page of Doom] - contains articles about the history of the ''Doom'' games
** [http://www.itplaysdoom.com/ It Plays Doom] - a database of the different gadgets ''Doom'' has been ported to
** [http://gh.ffshrine.org/soundtracks/209 Doom Soundtrack]

* WADs and fan creations
** [http://www.doomworld.com/idgames Doomworld's web interface to the comprehensive idgames FTP archive]
** [http://www.doom2.net/~compet-n/index.cgi Compet-N] - [[Compet-N]] - the main [[Doom speedrunning|''Doom'' speedrunning]] site
** [http://doom.ocremix.org/ The Dark Side of Phobos] - unofficial album with rearranged ''Doom'' music
** [http://www.doomwadstation.com/ Doom Wad Station] - Thousands of maps ready for download!

{{DOOMgames}}

<!-- Additional categories for ("Linux games", "PlayStation games", etc) are at [[Doom versions and ports]] -->
[[Category:Doom|*]]
[[Category:1993 computer and video games]]
[[Category:First-person shooters]]
[[Category:DOS games]]
[[Category:Atari Jaguar games]]
[[Category:DOS games converted into Windows games]]
[[Category:Multiplayer online games]]
[[Category:Banned computer and video games]]
[[Category:Controversial computer and video games]]

Original Wiki source: [http://en.wikipedia.org/ Wikipedia]