Original owners
John Carmack, technical director

John Romero, level artist

Adrian Carmack, artist

Tom Hall, Game designer

Game development

Technology
 

John Carmack at the 2010 GDC

Starting with their first shareware game series, Commander Keen, Id Software has licensed the core source code for the game, or what is more commonly known as the engine. Brainstormed by John Romero, Id Software held a weekend session titled "The Id Summer Seminar" in the summer of 1991 with prospective buyers including Scott Miller, George Broussard, Ken Rogoway, Jim Norwood and Todd Replogle. One of the nights, Id Software put together an impromptu game known as "Wac-Man" to demonstrate not only the technical prowess of the Keen engine, but also how it worked internally.

Id Software has developed their own game engine for each of their titles when moving to the next technological milestone, including Commander Keen,Wolfenstein 3D, ShadowCaster, Doom, Quake, Quake II, and Quake III, as well as the technology used in making Doom 3. After being used first for Id Software's in-house game, the engines are licensed out to other developers. According to Eurogamer.net, "Id Software has been synonymous with PC game engines since the concept of a detached game engine was first popularised". During the mid to late 1990s, "the launch of each successive round of technology it's been expected to occupy a headlining position", with the Quake III engine being most widely adopted of their engines. However Id Tech 4 had far fewer licensees than the Unreal Engine from Epic Games, due to the long development time that went into Doom 3 which Id had to release before licensing out that engine to others.

In conjunction with his self-professed affinity for sharing source code, John Carmack has open-sourced most of the major Id Software engines under the General Public License. Historically, the source code for each engine has been released once the code base is 5 years old. Consequently, many home grown projects have sprung up porting the code to different platforms, cleaning up the source code, or providing major modifications to the core engine. Wolfenstein 3D, DOOM andQuake engine ports are ubiquitous to nearly all platforms capable of running games, such as hand-held PCs, iPods, the PSP, the Nintendo DS and more. Impressive core modifications include DarkPlaces which adds stencil shadow volumes into the original Quake engine along with a more efficient network protocol. Another such project is ioquake3, which maintains a goal of cleaning up the source code, adding features and fixing bugs.

The GPL release of the Quake III engine's source code was moved from the end of 2004 to August 2005 as the engine was still being licensed to commercial customers who would otherwise be concerned over the sudden loss in value of their recent investment.

On August 4, 2011, John Carmack revealed during his QuakeCon 2011 keynote that they will be releasing the source code of the Doom 3 engine (Id Tech 4) during the year.
Id Software publicly stated they would not support the Wii console (possibly due to technical limitations), although they have since indicated that they may release titles on that platform (although it would be limited their games released during the 1990s).

Since Id Software revealed their engine Id Tech 5, they call their engines "Id Tech", followed by a version number. Older engines have retroactively been renamed to fit this scheme, with theDoom engine as Id Tech 1.

Linux gaming

 

Timothee Besset has been responsible for many Linux ports of Id Software's games

Id Software was an early pioneer in the Linux gaming market, and Id Software's Linux games have been some of the most popular of the platform. Many Id Software games won the Readers' and Editors' Choice awards of Linux Journal. Some Id Software titles ported to Linux are Doom (the first Id Software game to be ported), Quake, Quake II, Quake III Arena, Return to Castle Wolfenstein, Wolfenstein: Enemy Territory, Doom 3, Quake 4, and Enemy Territory: Quake Wars. Since Id Software and some of its licencees released the source code for some of their previous games, several games which were not ported (such as Wolfenstein 3D, Spear of Destiny, Heretic, Hexen, Hexen II, and Strife) can run on Linux and other operating systems through the use of source ports.

The tradition of porting to Linux was first started by Dave D. Taylor with David Kirsch doing some later porting. Since Quake III Arena Linux porting has been handled by Timothee Besset. The majority of all Id Tech 4 games, including those made by other developers, have a Linux client available, the only current exceptions being Wolfenstein and Brink. Similarly, almost all of the games utilizing the Id tech 2 engine have Linux ports, the only exceptions being those created by Ion Storm. Despite fears by the Linux gaming community that Id Tech 5 would not be ported to that platform, Timothee Besset in his blog has stated "I'll be damned if we don't find the time to get Linux builds done". Besset has stated that Id Software's primary justification for releasing Linux builds is better code quality, along with a technical interest for the platform.

John Carmack has expressed his stance with regard to Linux builds in the past. Todd Hollenshead has also expressed support for Linux: "All said, we will continue to be a leading supporter of the Linux platform because we believe it is a technically sound OS and is the OS of choice for many server ops." However Carmack revealed that "there are no plans for a native Linux client" of id's most recent game, Rage.

Games
Commander Keen
The Commander Keen series, a platform game introducing one of the first smooth side-scrolling game engines for MS-DOS, brought Id Software into the gaming mainstream. The game was very successful and spawned a whole series of titles. It was also the series of Id Software that designer Tom Hall was most affiliated with.

Wolfenstein
Main article: Wolfenstein (series)

The company's breakout product was 1992's Wolfenstein 3D, a first person shooter (FPS) with smooth 3D graphics that were unprecedented in computer games, and with violent gameplay that many gamers found engaging. After essentially founding an entire genre with this game, Id Software created Doom, Doom II, Quake, Quake II, Quake III Arena, Quake 4 and Doom 3. Each of these first person shooters featured progressively higher levels of graphical technology. Wolfenstein 3D spawned a prequel and a sequel, the prequel called Spear of Destiny, and the second, Return to Castle Wolfenstein, used the Id Tech 3 engine. A third Wolfenstein sequel, simply titled Wolfenstein, has been released by Raven Software, using the Id tech 4 engine.

Doom
Main article: Doom (series)
Eighteen months after their release of Wolfenstein 3D, in 1993 Id Software released Doom which would again set new standards for graphic quality and graphic violence in computer gaming. Doomfeatured a sci-fi/horror setting with graphic quality that had never been seen on personal computers or even video game consoles. Doom became a cultural phenomenon and its violent theme would eventually launch a new wave of criticism decrying the dangers of violence in video games. Doom was ported to numerous platforms, inspired many knock-offs and was eventually followed by the technically similar Doom II. Id Software made its mark in video game history with the shareware release of Doom, and eventually revisited the theme of this game in 2004 with their release ofDoom 3. John Carmack said in an interview at QuakeCon 2007 that there will be a Doom 4, it has been in development since May 7, 2008.