Doom (officially cased DOOM) is a 1993 computer game by id Software that is a landmark title in the first-person shooter genre, and in first person gaming in general. It is widely recognized for pioneering immersive 3D graphics, networked multiplayer gaming on the PC platform, and support for custom expansions (WADs). 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 effect on the industry, games from the mid-1990s boom of first-person shooters are often known simply as "Doom clones". Its graphic and interactive violence has also made Doom the subject of much controversy reaching outside the gaming world. According to GameSpy, Doom was voted by industry insiders to be the greatest game of all time in 2004.
The Doom franchise was continued with Doom II: Hell on Earth (1994) and numerous expansion packs, including The Ultimate Doom (1995), Master Levels for Doom II (1995), and Final Doom (1996). Originally released for PC/DOS, these games have later been ported to many other platforms, including nine different game consoles, Rockbox firmware, and even PDAs. The series lost mainstream appeal as the technology of the Doom game engine was surpassed in the mid-1990s, although fans have continued making WADs, speedruns, and modifications to the source code 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 motion picture.
The player takes the role of a space marine, "one of Earth's toughest, hardened in combat and trained for action", who has been deported to Mars as punishment for assaulting a senior officer when ordered to attack civilians. He forms part of a force stationed in the area where the Union Aerospace Corporation (UAC), a multi-planetary conglomerate, is performing secret experiments with teleportation between the moons of Mars, Phobos and Deimos. The marine seems to have been forced into a security or unimportant staff position according to the manual, stating that "with no action for fifty million miles, your day consisted of suckin' dust and watchin' restricted flicks in the rec room." Suddenly, computer systems on Phobos behave wildly and unpredictably, and "something friggin' evil" comes out of the teleporters, called "gateways". An emphatic call for assistance is made to Mars as the bases get overrun, but all personnel are killed or possessed. At the same time, Deimos vanishes entirely. The military unit is sent to Phobos to investigate the incident, and the player character is left to guard the hangar as the rest of the group proceeds. Radio signals filled with gunfire and other signs of violence indicate the group engages the invaders, and eventually it becomes apparent that the marine is all alone on hostile Phobos.
In order for the game to be completed, the marine must fight through Phobos, Deimos, and then Hell, each presented as an episode containing nine distinct levels. 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 character fighting a pair of Barons of Hell and afterwards entering the teleporter leading to Deimos, ending with him getting overwhelmed by monsters, if not killed. In the second episode, the Shores of Hell, the character journeys through the installations on Deimos, whose areas are interwoven with beastly architecture, warped and distorted by the hellish invasion. After defeating the titanic Cyberdemon lord, he discovers the truth about the vanished moon: it is floating above Hell. After climbing down to the surface, the third episode begins, called Inferno. After the huge Spiderdemon that masterminded the invasion is destroyed a hidden doorway back to Earth opens for the hero, who has "proven too tough for Hell to contain".
The Ultimate Doom, the retail store version of the game, adds a fourth episode, Thy Flesh Consumed, occurring after the three original episodes of Doom and before Doom II.
Being a first-person shooter, Doom is experienced through the eyes of the main character. This character is not named throughout the game, and one of the game's designers, John Romero, has pointed out that this is so the player feels more involved in the game: "There was never a name for the DOOM marine because it's supposed to be YOU.
The objective of each level is simply to locate the exit room that leads to the next area, usually marked with an exit sign or a special kind of door, while surviving all hazards on the way. Among the obstacles are monsters, pits of toxic or radioactive slime, ceilings that come down and crush the player character, and locked doors for which a keycard, skull-shaped key device, or remote switch needs to be located. The levels are sometimes labyrinthine and feature plenty of hidden secret areas that hold power-ups as a reward for players who explore. To ease navigation through the levels, a full screen automap is available.
Doom is notable for the weapons arsenal available to the marine, which became prototypical for first-person shooters. The player character starts armed only with a pistol, and brass-knuckled fists 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 character's ammunition-carrying capacity, armor, first aid kits to restore health, the berserk pack (a dark first aid box that puts the character into berserk mode, allowing them to deal out rocket launcher-level damage with their fists and potentially splattering former humans and imps, as well as setting the user's health to 100% if it was lower), and supernatural blue orbs (named soul spheres in the manuals) that boost the player character's health percentage by 100%, up to a maximum of 200%.
The enemy monsters in Doom make up the central gameplay element. The player character faces them in large numbers, on the higher of the game's five difficulty levels 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 specifically hellish monsters of varying strength, including the weak but ubiquitous imps, the floating cacodemons, and the bosses which survive multiple strikes even from the player character's strongest weapons. The monsters have very simple behavior, consisting of either walking toward their opponent, or attacking by throwing fireballs, biting, and scratching. They may also sometimes fight each other after hurting one another accidentally.
Many versions of Doom (and its sequels) include secret levels which are accessed by the player discovering alternate exits, often hidden behind secret doors or in areas which are difficult to reach. In some versions of Doom II two of these secret levels incorporate level design and characters from Doom's precursor, Wolfenstein 3D.
Aside from the single player game mode, Doom features two multiplayer modes playable over a network: "cooperative", in which two to four players team up, and "deathmatch", in which two to four players play against each other.
The development of Doom started in 1992 when John D. Carmack developed a new 3-D game engine, the Doom engine, while the rest of the id Software team finished the Wolfenstein 3D prequel, Spear of Destiny. When the game design phase began in late 1992, the main thematic influences were the science fiction action movie Aliens and the horror movie Evil Dead II. The title of the game was picked by Carmack:
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. 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 built from sculptures in clay or latex, and some of the weapons are toy guns from Toys "R" Us. A heavy metal-ambient soundtrack was supplied by Bobby Prince.
In contrast to the static levels of Wolfenstein 3D, those in Doom are highly interactive: platforms can lower and rise, floors can rise sequentially to form staircases, and bridges can rise and descend. 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 growls 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 home computers of 1993. Most significantly, Doom levels are not truly three-dimensional; they are internally represented on a plane, with height differences added separately (a similar trick is still used by many games to create huge outdoor environments). This gives the appearance of a two point perspective projection, and 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 method. Another benefit was the clarity 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 WAD files. Wolfenstein 3D was not designed to be expandable, 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 below).
Doom was released as shareware, with people encouraged to distribute it further. They 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.
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 networks 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 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. The Microsoft 1995 release Excel 95 included a Doom-esque secret level as an easter egg containing portraits of the programmers among other things. It is speculated that Microsoft engineers took advantage of their experience working on the Doom Windows 95 port to place the code in the spreadsheet program.
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—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 multiplayer was also possible over a phone line by using a modem, or by linking two PCs with a null-modem cable. 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").
The ability to create custom levels and otherwise modify the game, in the form of custom WAD files, turned out to be a particularly popular aspect of Doom. Gaining the first large mod-making community, Doom affected the culture surrounding first-person shooters, and also the industry. Several to-be professional game designers 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 editors 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, other video games and other brands from popular culture have been turned into Doom WADs by fans (without authorization), including Aliens, Star Wars, The X-Files, The Simpsons, South Park, Sailor Moon, Dragon Ball Z, Red Faction, Pokémon , and Batman. Some works like the Theme Doom Patch even combined enemies from several movies like Aliens, Predator and The Terminator.
Some add on 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 fake orgasm scene from When Harry Met Sally....
Around 1994 and 1995, WADs were primarily distributed online over bulletin board systems or sold in collections on compact discs 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, 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 in order to run. A typical launcher would allow the player to select which files to load from a menu, making it much easier to start.
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 consoles and operating systems 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 NES, Sega 32X, Sony PlayStation, Game Boy Advance, RISC OS, Atari Jaguar, Sega Saturn, Nintendo 64, Tapwave Zodiac, 3DO, Xbox as a feature of Doom 3: Limited Edition, and Xbox 360 on Xbox Live Arcade. The total number of copies of Doom games sold is unknown, but may be well over 4 million; Doom II alone has earned over $100 million in total sales.
The game engine was licensed to several other companies as well, who released their own games based on it, including 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's release, and they were often referred to as "Doom clones" rather than "first-person shooters". Some of these were certainly "clones"—hastily assembled and quickly forgotten about—others explored new grounds of the genre and were highly acclaimed. Many of the games closely imitated features in Doom such as the selection of weapons and cheat codes. Doom's principal rivals were Apogee's Rise of the Triad and Looking Glass Studios' System Shock (which, unlike Doom, featured true 3D gameplay). 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.
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, id Software had nearly finished Quake, its next-generation game, which mirrored Doom'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 hyped 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 comic book, four novels by Dafydd Ab Hugh and Brad Linaweaver (loosely based on events and locations in the games), and a film starring Karl Urban and 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.
Doom was and remains notorious for its high levels of violence, gore, and satanic imagery, which have generated much controversy from a broad range of groups. Yahoo! Games has it listed as one of the top ten controversial games of all time. It has been criticized numerous times by religious organizations for its diabolic undertones and was dubbed a "mass murder simulator" by critic and Killology Research Group founder David 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 Phil Talmadge to introduce compulsory licensing of VR use.
The game again sparked controversy throughout a period of school shootings 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". 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 his role in the shootings by playing these levels over and over. Although Harris did design Doom levels, they were not simulations of Columbine High School.
While Doom and other violent video games have been blamed for nation-wide school shootings, recent research featured by Greater Good Science Center shows that the two are not closely related. Harvard medical school researchers Cheryl Olson and Lawrence Kutner found that violent video games did not correlate to school shootings. The U.S. Secret Service and Department of Education analyzed 37 incidents of school violence and sought to develop a profile of school shooters, they discovered that the most common traits among shooters were that they were male and had histories of depression and attempted suicide. While many of the killers- like the vast majority of young males- did play video games, this study did not find a relationship between game play and school shootings. In fact, only one eighth of the shooters showed any special interest in violent video games, far less that the number of shooters who seemed attracted to books and movies with violent content.
Although the popularity of the Doom games dropped with the release of Descent (1995), Duke Nukem 3D (1996) and Quake (1996), the game had still retained a strong fan base that continues to this day by playing competitively and creating 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, Nintendo DS, TI calculators, the iPod and most recently the Wii. As for the PC, there has been additions of 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 ports, some of which remain under active development.
Devoted players have spent years creating speedruns for Doom, competing for the quickest completion times and sharing knowledge about routes through the levels and how to exploit bugs 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 more aggressive, launch faster projectiles (or, in the case of the Pinky Demon, simply move faster), and respawn roughly 30 seconds after they have been killed (level designer John Romero characterized the idea of such a run as "[just having to be] impossible). Movies of most of these runs are available from the COMPET-N website.
Online co-op and deathmatch play still continues on servers listed through services such as Odamex, Skulltag and ZDaemon.