| Activation limit | A copy protection scheme where a purchased game has - usually very small - limit on the number of "activations" before you're supposed to re-purchase or renew your previous license for the game. |  | 2006 / 2009 | 6 games |
| Ada Computer Language | | | | 0 games |
| Adventure Game Interpreter | "AGI (Adventure Game Interpreter) was the development tool used by Sierra Online to create their early adventure games." [Source: Wikipedia] | | 1984 / 1988 | 15 games |
| Adventure Game Studio (AGS) | Made using AGS, a game engine and development tool for creating point and click adventure games. |  | 2003 / 2010 | 26 games |
| AI middleware (Artificial Intellligence middleware;AI libraries) | | | | 0 games |
| AIX operating system | A UNIX-like proprietary IBM OS. Closed source, but most games are Open Source. Originally Advanced IBM UNIX. Currently, Advanced Interactive eXecutive | | 1989 / 1996 | 10 games |
| Alamo game engine | A game engine created by Petroglyph Games. | | 2006 / 2008 | 5 games |
| Allegro Library | A cross-platform game oriented programming library. | | 1999 / 2009 | 103 games |
| ALT Linux Sisyphus | A set of Linux distros specializing in customization, correct localization, and advanced package management. | | 2001 / 2003 | 5 games |
| Alterforce Engine | A game engine for gem-swap games by Smartpix Games | | | 2 games |
| Anamorphic resolution | Anamorphic projection squeezes an image, usually horizontally, expecting it to be stretched out on the screen so that the final image appears normal. | | 1997 / 2008 | 4 games |
| Android Operating System | An OS optimized for mobile devices & based on an independent fork of the Linux kernel. | | 2008 / 2012 | 288 games |
| Anti-cheat (Anti-hack) | Any and all anti-cheat/hack solutions. | | | 0 games |
| AppleDOS 3.3 | Games that operated on Apple's AppleDOS version 3.3. Either internally (boot disk) or could be loaded on a system running 3.3. | | | 1 games |
| AppleTalk | AppleTalk is a set of proprietary networking protocols developed 1984 by Apple for use with the Mac, OSX, ][c, & accessories. Discontinued 2009. | | 1984 / 1998 | 6 games |
| Application Programming Interfaces | | | | 0 games |
| Arch Linux | A minimalist distro designed elegant, code correct, lightweight, & simple from a developers point of view. Relies heavily on command-line utilities. | | | 0 games |
| Arch Linux | A minimalist distro designed elegant, code correct, lightweight, & simple from a developers point of view. Relies heavily on command-line utilities. | | 1996 / 2012 | 29 games |
| Archive Games | This game is available through the Archive Games distribution/shopping service. | | 1989 / 2009 | 12 games |
| AROS (AROS Research Operating System;Amiga Research Operating System) | AROS is a non-propriety implementation of the AmigaOS 3.1 APIs. Source-compatible not binary-compatible; designed so AmigaOS code will compile on it. | | | 1 games |
| Assembly language (ASM) | Written in assembly language, a human readable form of machine code. The least portable of computer languages & lowest level that can still be considered a language. | | 1979 / 2008 | 91 games |
| AtmosFear engine | A game engine by Action Forms. |  | 1998 / 2005 | 4 games |
| Audio middleware (Sound engines;Audio libraries) | | | | 0 games |
| Automatic aspect ratio | Handles almost any aspect ratio from regular 4:3 to widescreen to vertical screen without effort, with possibly only very few limitations (such as square pixels). | | 1995 / 2010 | 14 games |
| Automatic wide aspect ratio | Can attempt to automatically adjust to wide aspect ratios besides those it supports directly. | | 2005 / 2008 | 3 games |
| BASIC programming language (Beginner's All-purpose Symbolic Instruction Code) | Coded in BASIC. | | 1972 / 2009 | 372 games |
| BASICA Programming Language | Games that use BASICA source code. | | | 1 games |
| batari (bB) | Batari is a BASIC-like language compiler for developing Atari VCS games. There is also a Visual batari Basic IDE application. | | | 1 games |
| Battle.net (bnet) | Utilizes Blizzard's Battle.net matchmaking and internet lobby services. | | 1995 / 2012 | 24 games |
| BattleZone engine | | | 1998 / 2000 | 3 games |
| bBasic programming language | Written in bBasic. A BASIC-like language that creates compiled Atari 2600 binary files suitable for emulators or creating Atari 2600 cartridges. | | | 1 games |
| BBS door | | | | 0 games |
| Bell Labs UNIX | Games that run on a specific UNIX OS distributed by Bell Labs | | | 1 games |
| BeOS (ZetaOS) | Runs on the BeOS Operating System. | | 1990 / 2010 | 479 games |
| Big Huge Engine | A game engine by Big Huge Games. | | 2003 / 2007 | 4 games |
| Bink Video codec | .bik files developed by RAD Game Tools. Uses up to 16 different techniques per file to optimize decoding times rather than achieving best compression | | 2000 / 2012 | 48 games |
| Boss button (Boss key) | Includes a hotkey to display a fake screen or quickly hide the game, creating an illusion of serious work. Used to try to fool a boss or just to keep onlookers from knowing a game is being played. | | 1986 / 2000 | 14 games |
| Browser-based | Played in a regular internet HTTP browser. Usually requires account registration, but not always even that. | | 1998 / 2012 | 55 games |
| BSD operating system | Games that run on BSD by Berkeley Software Design, Inc.
BSD is derived from UNIX & thanks to a very permissive license, has influenced subsequent UNIXs & many other OS including MacOSX, WinXP and Solaris. | | 1993 / 2011 | 20 games |
| BSDi v4 operating system | Games that run on version 4 of the official BSD operating system provided by Berkeley Software Design, Inc. | | 1992 / 1996 | 2 games |
| Bug: Thread sync missing | Fails to synchronize threads, causing inexplicable crashes on multi-core systems while seemingly running fine on single-core systems. | | 1999 / 2005 | 2 games |
| C programming language | Coded in C, a general-purpose programming language, originally designed by Dennis Ritchie. | | 1971 / 2012 | 167 games |
| Caldera Linux | | | | 1 games |
| CentOS Linux Distribution | Games for the CentOS operating system. CentOS promises 100% compatibility with Red Hat Linux | | 2005 / 2006 | 4 games |
| Chipmunk Physics Engine | | | | 0 games |
| clanlib | Cross platform C++ toolkit library. Its primary focus is on games. | | 2001 / 2012 | 12 games |
| Classic Mac OS | Games for Mac OS 9 or earlier. | | 1984 / 2004 | 34 games |
| CloakNT game engine (Cloak engine) | A game engine by Cauldron. | | 2003 / 2007 | 7 games |
| Closed Captioning (CC;Subtitles 888) | Closed captioning is visual information about the audio of a game that is generally intended for the hearing impaired. | | 1997 / 2010 | 26 games |
| Comes in a Debian package | Other distros beside [[gametag:debian Debian]] can use theses packages also. | | 1993 / 2012 | 89 games |
| Compatibility | Any and all tags relating to software and hardware compatibility. | | | 0 games |
| Compatible with WINE | Works [b]normally[/b] with at least 1 version of WINE compatibility layer for Linux, simply by installing it, the same as if you were running it on Windows | | 1992 / 2012 | 57 games |
| Control config (User configurable controls) | Allows changing controls, keyboard mappings, button layout, etc. to better suit the user. | | 1992 / 2011 | 66 games |
| Control layouts (Control presets;Multiple predefined control layouts) | Offers several predefined control layouts but no full customization, nor are these different control schemes. | | 2002 / 2009 | 4 games |
| Corel LinuxOS distribution | Games that run on Corel Linux, a Debian-based distro. Used custom GUI, looked like Win98. Migration was very easy. M$ stole its File & Settings Transfer Wizard. | | | 1 games |
| CP/M OS | An operating system that reached its peak just before the IBM-PC was released. It rapidly lost its market share to MS-DOS compatible OSes. | | 1978 / 1992 | 38 games |
| Crap Adventure Construction Kit | | | | 1 games |
| CryENGINE 2 | | | 2003 / 2009 | 6 games |
| Crystal Space 3D engine | An Open Source 3D graphics engine. | | 2006 / 2011 | 14 games |
| Crystal Tools engine | A game engine by Square Enix. | | 2009 / 2011 | 4 games |
| Curses | A library for implementing GUI & graphic looking applications using only text display. | | 1986 / 2006 | 11 games |
| Customizable anamorphic aspect ratio | The resolution & aspect ratio are fully independent and customizable. | | | 2 games |
| D programming language (DMD;Digital Mars D) | A programming language created by Walter Bright of Digital Mars. | | 2002 / 2008 | 17 games |
| Dark Basic programming language | Game is written in Dark BASIC computer language. | | 2000 / 2007 | 2 games |
| DART (Direct Audio Real Time) | A sound API & corresponding DLL that allows OS/2 applicators to have multiple levels of direct access to audio hardware. | | 1997 / 2002 | 21 games |
| DASM Assembler | A tool for programming in assembly | | | 1 games |
| Data only | Released as data only, requiring the player to find a game engine to run it on. Likely platform-independent. | | | 3 games |
| Debian GNU/Linux | Games for Debian distro. The most tightly organized GNU OS available. | | 1988 / 2012 | 169 games |
| DemonWare middleware | Networking middleware by DemonWare Ltd. (owned by Activision since 2007/02) | | 2005 / 2007 | 8 games |
| Development System used ran the NeXTSTEP/68000 OS | These games were developed in part or whole using at least 1 computer with a 68000 cpu running the NeXTSTEP OS. | | 1993 / 1996 | 4 games |
| Development System used ran the NeXTSTEP/Intel OS | These games were developed in part or whole using at least 1 computer with an Intel 80386 cpu running the NeXTSTEP OS. | | 1993 / 1996 | 3 games |
| Development System used ran the NeXTSTEP/PPC OS | These games were developed in part or whole using at least 1 computer with a PowerPC cpu running the NeXTSTEP OS. | | 1993 / 1996 | 3 games |
| Development System used was running a Linux based OS | These games were developed in part or whole using at least 1 Linux based system. | | 1996 / 2010 | 6 games |
| Development System used was running MacOS X | These games were developed in part or whole using Mac OS X. | | 2004 / 2011 | 2 games |
| Diesel engine | A game engine developed by GRIN. | | 2001 / 2009 | 11 games |
| Direct3D | Uses or can use Direct3D for graphics. | | 1996 / 2010 | 36 games |
| DirectMusic (Interactive Music Architecture) | A depreciated subset of the DirectSound API that allowed high level access to hardware through DirectSound. Not available to 64-bit systems. | | 2000 / 2002 | 4 games |
| DirectX 1.0 (DX1) | Supports or requires DX1 run-times to be present. | | 1998 / 1998 | 2 games |
| DirectX 2 (DX2) | Supports or requires DX2 run-times to be present. | | 1996 / 1999 | 4 games |
| DirectX 3 (DX3) | Supports or requires DX3 run-times to be present. | | 1996 / 2006 | 18 games |
| DirectX 5 | Supports or requires DX5 run-times to be present. | | 1997 / 2007 | 43 games |
| DirectX[DX] | | | | 0 games |
| Display Control Interface | a predecessor to DirectDraw. | | | 0 games |
| DIVE (Direct Interface Video Extentions) | A dynamic recompilation graphics API & corresponding DLL allowing OS/2 applications direct access to video hardware. DIVE predates DirectX/DirectDraw. | | | 29 games |
| DoJa | A custom Java for DoCoMo's i-mode mobile phone platform. | | | 1 games |
| DoomRPG engine | Uses DoomRPG's game engine | | 2005 / 2007 | 3 games |
| DreamWorld engine | | | 2008 / 2012 | 4 games |
| DRM removed (Copy protection removed) | Games that originally were copy protected but had it removed in some officially released patch or re-release. | | 1992 / 2012 | 31 games |
| DRM: Pinhole Copy Protection | Primitive DRM method of puncturing a specific point of a master floppy disk. If the game can read & write the damaged sector, it knows its being played from a copy | | | 2 games |
| DSiWare | Distributed through Nintendo's DSiWare online service for the Nintendo DSi handheld console. | | 2008 / 2011 | 35 games |
| Dynamic Universal Music Bibliotheque (DUMB) | DUMB is an IT, XM, S3M and MOD player library developed by Robert J Ohannessian, Julien Cugnière and Ben Davis. | | 2001 / 2007 | 12 games |
| Dynamix Game Development System (dgds) | A game engine and system of development tools by Dynamix used for several of their games. | | 1990 / 1992 | 9 games |
| ECMAScript (JavaScript;JScript;ECMA-262;ISO/IEC 16262) | Coded wholly or partially in ECMAScript or is extensible with it. Including any of its dialects such as JavaScript or JScript. | | 2007 / 2012 | 10 games |
| EDGE (Enhanced Doom Game Engine) | A modernized DOOM engine that still remains compatible with the originals. | | | 1 games |
| Eduke32 Engine | A game engine that plays Duke Nukem and other games. | | | 0 games |
| EKI One | A game development suite. | | | 4 games |
| Emulation | | | | 0 games |
| Enigma engine (Blitzkrieg engine) | Game engine developed by Nival. | | 2003 / 2008 | 8 games |
| ExEn (Execution Engine) | By In-Fusio. Aims to be less limited than J2ME. Built-in scaling, parallaxing, raycasting, & rotation. Available under "premium" or "free" licenses. | | | 1 games |
| Explore Engine | Joseph Peterson & De Crandell's BASIC engine for the TRS-80 computer. A generic way to create adventure games inspired by Colossal Cave Adventure. | | | 5 games |
| Export data for use in another game. | Probably characters for a sequel, but any type data counts. | | 1987 / 2010 | 23 games |
| Extraneous data accidentally included | Unintended data included in production copies. For instance, the master copy disk had personal letter that was not overwritten by the game's data. | | | 1 games |
| Familiar Project (Familiar Linux) | Complete OS with OPIE or GPE GUI intended for iPAQ, Agenda or other PDAs. Based on a kernel modified by Compaq who officially switched iPAQ to Familiar | | | 3 games |
| Famitracker NES music development software | Music was developed in full or part using the Famitracker software. | | | 1 games |
| Fargo II Shell | Fargo II is an OS shell for the TI-92 calculator | | | 0 games |
| Fast Light Toolkit (FLTK) | Allows creation of complete games quickly without sacrificing graphics & GUI or taxing the end users' hardware. Includes 3D, OpenGL, & emulates GLUT. | | | 1 games |
| Fedora Core Linux | Games that run on the Fedora Core Distro. Fedora is the 'free' version of Red Hat Enterprise Linux. | | 1979 / 2012 | 70 games |
| Fenix computer language | | | | 1 games |
| ffdshow incompatibility | Games that exhibit issues of varying severity with ffdshow installed. | | 1999 / 2003 | 4 games |
| Fighter Maker | Created with Enterbrain's 2D Fighter Maker. | | | 2 games |
| flatzebra Engine | A GPL generic game engine for 2D double-buffering animation using SDL by Pierre Sarrazin | | 2000 / 2004 | 8 games |
| Flixel Engine | A completely free (personal or commercial) opensource game-making library. Written entirely in Actionscript 3, & designed for use with free development tools | | 2011 / 2012 | 3 games |
| Fortran programming language | General-purpose language most suited for numeric and scientific computing. High-level languages were only theory before Fortran because they were considered inherently slower than handwritten assembly. | | 1975 / 1979 | 6 games |
| Frame synced (Frame synced logic) | Game speed and background logic is synced with drawn frames. | | 1982 / 2007 | 14 games |
| FreeBSD OS | Games that run on FreeBSD. A reliable variation of BSD with any code removed that might be legally questioned. Can achieve 99.95% or more up time. | | 1979 / 2012 | 119 games |
| Freespace Engine | A game engine with loosely interpreted outer space physics used for the Freespace series of games. | | 1998 / 2010 | 11 games |
| Fullscreen only | Runs only in fullscreen. | | 1996 / 2011 | 23 games |
| Gambas programming language | [b]G[/b]ambas [b]A[/b]lmost [b]M[/b]eans [b]Bas[/b]ic
An object-oriented dialect of the BASIC with it's own IDE that somewhat mimics Visual Basic. | | | 1 games |
| Game engines | This is a parent group for game engines. | | | 0 games |
| Game Maker | Made with Game Maker. | | 2003 / 2012 | 17 games |
| Game makers (Game development environments) | Any software that exists to make making games as simple, easy and efficient as possible. | | | 0 games |
| Game Oriented Object LISP 2 Engine (GOOL 2 Engine) | | | | 0 games |
| Game saves | Any tag that describes when or where the game can be saved, but does not include on what the saves are stored if anything. | | | 0 games |
| Games for Windows - LIVE (XLive;GfWL) | Uses the Windows LIVE online service. Similar to Xbox Live and actually bridges over to it. | | 2007 / 2012 | 33 games |
| GameSpy (GameSpy Arcade) | Uses GameSpy's multiplayer matchmaking service. This may require an unique account at GameSpy. | | 1998 / 2011 | 73 games |
| Garry Kitchen's Gamemaker (Activision Gamemaker) | Games made with Garry Kitchen's Gamemaker IDE.
| | 1985 / 1986 | 2 games |
| GCOS (General Comprehensive Operating System;GECOS;General Electric Comprehensive Operating System) | A multithreaded OS originally by General Electric that was designed for mainframes & batch processing. Remains in use through emulation for legacy operations. | | | 0 games |
| GCOS (General Comprehensive Operating System;GECOS) | Later renamed GECOS (the [b]G[/b]eneral [b]E[/b]lectric [b]C[/b]omprehensive [b]O[/b]perating [b]S[/b]upervisor) | | | 1 games |
| Geeny Engine | A game engine by Sinister Systems | | | 0 games |
| Genie Engine | A game engine developed by Ensemble Studios | | 1997 / 2002 | 6 games |
| Gentoo Linux (Gentoo/FreeBSD) | Games for Gentoo. Gt and apps come in source code not binary form. This is so the user-compiled apps are optimized and fast. Its BSD based. | | 1991 / 2011 | 87 games |
| GIMP Toolkit (GTK;GTKmm;GTK+) | Uses GTK. | | 1990 / 2010 | 9 games |
| Glulx VM | Like Z-machine but uses 32-bit and Glk I/O. Plays game written in inform language. Games with this tag will [b][i]only[/i][/b] run on Glulx VM implementations. | | | 1 games |
| Gnome Desktop Environment | Requires Gnome, a Linux/X11 desktop environment. | | 1988 / 2005 | 37 games |
| Godfather engine | | | 2006 / 2008 | 11 games |
| Graphics middleware (Graphics engines;Graphics libraries) | | | | 0 games |
| Graphics techniques | | | | 0 games |
| Grim Engine (GrimE) | Game engine developed by LucasArts, incorporating the older Sith engine. | | 1998 / 2001 | 3 games |
| Haaf's Game Engine (HGE) | By Relish Games. For quickly making hardware accelerated 2D games without having to know a lot about technology. | | 2009 / 2011 | 3 games |
| Haiku OS | Haiku is a modern replacement for x86 BeOS running on x86, Arm, PowerPC, 68k, MIPS & possibly other CPUs. x86 BeOS compatibility requires and x86 CPU. | | 1990 / 2011 | 385 games |
| Haskell Computer Language | | | | 0 games |
| HawkNL™ (Hawk Network Library) | A free LGPL low level network API for games.
| | | 2 games |
| Heat.net | Uses SegaSoft's online service Heat.net, based on MPlayer. | | 1997 / 2000 | 3 games |
| HP-UX OS (Hewlett Packard UniX) | Games run on HP-UX. HP's version of UNIX System V. It is the reason an HP tech can pull up your file in the time it takes a Dell tech to say "Please Hold" | | 1991 / 2005 | 18 games |
| HPL1 engine | Game engine created by Frictional Games | | 2007 / 2008 | 10 games |
| HURD | Runs on the HURD microkernal, the intended core of the GNU operating system. | | 2003 / 2006 | 5 games |
| Import data created by another game | Probably characters from a prequel, but any type data counts. | | 1986 / 2012 | 41 games |
| iMUSE (Interactive Music Streaming Engine) | An interactive/adaptive music engine by LucasArts. | | 1991 / 1995 | 9 games |
| Incompatibility: AMD Dual-Core Optimizer | Removed due to insignificance. | | 2000 / 2003 | 3 games |
| Incompatibility: Windows XP 64 | Removed due to insignificance. | | | 1 games |
| Infernal Engine | Game engine developed by Terminal Reality | | 2008 / 2009 | 5 games |
| Inform programming language | A programming language and design system for interactive fiction, created by Graham Nelson in 1993. | | 1993 / 1999 | 2 games |
| Installjammer | A cross-platform windows style installation tool. | | 2009 / 2010 | 2 games |
| IntelliJ IDEA by JetBrains | Games developed in part or fully using the IntelliJ Integrated Developer Environment. | | | 1 games |
| Interactive Fiction Engine | A proprietary game engine of interactive fictions. Created by Simutronics. | | 1987 / 2003 | 2 games |
| Inverse kinematics | Uses inverse kinematics or similar animation technique that tries to dynamically find the position of joints in respect to the desired end position, usually to connect a leg to solid surface. | | 1998 / 2012 | 31 games |
| iPod Linux operating system | Games for iPod Linux O/S. | | | 1 games |
| IRE game engine | A game engine similar to the one used for Ultima 6. Uses Allegro. | | 2003 / 2004 | 4 games |
| IRIX operating system | Games for SGI's IRIX OS. | | 1979 / 2006 | 29 games |
| irrKlang audio library | A cross-platform audio library/API by Ambiera. | | 2008 / 2011 | 11 games |
| ISACT | | | | 0 games |
| Isometric Cube Engine Studio | An engine for isometric games. | | | 0 games |
| Java language | Coded wholly or partially in Java or is extensible with it. | | 1997 / 2008 | 10 games |
| Java platfom | Runs on the Java platform. Ideally they work on any system with Java runtime environment available without any differences. | | 1979 / 2012 | 232 games |
| Java Platform, Micro Edition (Java 2 Platform, Micro Edition;Java ME) | A subset of Java for resource limited devices like cell phones, PDAs, & set-top boxes. | | 2003 / 2008 | 10 games |
| Jedi engine | A game engine by LucasArts. | | 1995 / 1997 | 2 games |
| JGame Engine | A Java based, widely cross-platform (Linux, Windows, Mac, Java, Mobile, Android, Flash, Webstart), 2D game engine with optional OpenGL. | | | 0 games |
| JGMOD | An add-on for Allegro programs to play MODs. By Jeffery Guan. | | 2001 / 2003 | 4 games |
| JOGL (Java OpenGL) | JOGL is a wrapper that allows Java to use OpenGL functions. | | | 1 games |
| jPCT | jPCT is a free 3D engine/API for Java. It has renderers for OpenGL, Swing/AWT, and well as ability to display in browsers.
| | | 3 games |
| K Desktop Environment | Requires KDE components, a desktop environment for X11. | | 2000 / 2011 | 9 games |
| kFreeBSD - Debian for the FreeBSD kernel | These run on a GNU/Debian distribution variant that uses the FreeBSD kernel and not the Linux kernel. Editors should note CPU architecture with tags | | 1999 / 2006 | 6 games |
| Klik | Klik aims to reduce an application to only 1 file (the executable) that runs from any location on any distro without being installed. | | 1988 / 2007 | 34 games |
| Knoppix Linux OS | Game runs on Debian-based Knoppix. Famous for being entirely CD runnable or other removable media. | | | 1 games |
| KRASS engine | | | 2001 / 2005 | 4 games |
| LaserLock (LaserLok) | A copy protection that involves unreadable files in a hidden LASERLOCK folder on the game CD. | | | 1 games |
| Lassie Adventure Game Engine | | | | 0 games |
| Launcher | Uses a launcher type startup application, often with various configuration, help, and other features easily available before player has chance to start the actual game. Login too is commonly part of the launcher if such is needed. | | 2002 / 2012 | 29 games |
| Letterbox | Uses letterboxing to allow unsupported aspect ratios to display correctly. | | 1995 / 2012 | 41 games |
| License: Partially GNU GPL (Partially GNU General Public License) | If only part of the game is release under the GPL license. Then this tag. applies. | | 1991 / 2010 | 29 games |
| Lighting and shadowing | | | | 0 games |
| Lindows Linux O/S (Linspire;LindowsOS;Lin---s;Lindash;Freespire) | Games for Lindows operating system | | 2002 / 2009 | 5 games |
| Linux distributions (Linux distros) | | | | 0 games |
| Linux Game Publishing Copy Protection (LGP Copy Protection) | Supposedly a key/name/password system designed for full legal copying & installation rights for legitimate buyers while discouraging illegal copies. | | 2001 / 2009 | 20 games |
| Lionengine | A platformer game engine by Byron 3D Games Studio available to the public. Used for Byron 3DGS' LIonheart remake & other projects. | | | 0 games |
| Living Battlefield engine | | | 1997 / 1998 | 2 games |
| Local save storage | Stores saves locally on some system default location. | | 2009 / 2011 | 3 games |
| LPMud driver (LDMud driver) | MUDs running on LPMud driver or any of its derivatives. LPMud is a powerful engine with very little hard-coded functionality besides the LPC interpreter, unlike many other MUD drivers which rely on hardcoded info. | | 1989 / 2001 | 5 games |
| LyN Engine | | | 2009 / 2010 | 4 games |
| Mac OS 1 (OS Classic 1;Mac System Software 1) | Runs natively on the Original Mac System 1 and is supported by the developers/publishers on it. | | 1984 / 1985 | 2 games |
| Mac OS 2 (OS Classic 2;Mac System Software 2) | Runs natively on Mac System 2 and is supported by the developers/publishers on it. | | | 0 games |
| Mac OS 3 (OS Classic 3;Mac System Software 3) | Runs natively on Mac System 3 and is supported by the developers/publishers on it. | | | 0 games |
| Mac OS 4 (OS Classic 4;Mac System Software 4) | Runs natively on Mac System 4 and is supported by the developers/publishers on it. | | | 0 games |
| Mac OS 5 (OS Classic 5;Mac System Software 5) | Runs natively on Mac System 5 and is supported by the developers/publishers on it. | | | 0 games |
| Mac OS 6 (OS Classic 6) | Runs natively on Mac OS 6 and is supported by the developers/publishers on it. | | 1985 / 1998 | 9 games |
| Mac OS 7 (OS Classic 7) | Runs natively on Mac OS 7 and is supported by the developers/publishers on it. | | 1985 / 1999 | 15 games |
| Mac OS 8 (OS Classic 8) | Runs natively on Mac OS 8 and is supported by the developers/publishers on it. | | 1985 / 2003 | 14 games |
| Mac OS 9 (OS Classic 9) | Runs natively on Mac OS 9 and is supported by the developers/publishers on it. | | 1985 / 2003 | 14 games |
| Mac OS X 10.1.x Puma | Requires at least version 10.1 of OS X. | | 2003 / 2008 | 6 games |
| Mac OS X 10.2.x Jaguar | Requires at least version 10.2 of OS X. | | 2000 / 2011 | 14 games |
| Mac OS X 10.5.x Leopard | Requires at least version 10.5 of OS X. | | 2008 / 2012 | 17 games |
| Mac OS X operating system | Games for OS X. Not inherently compatible with Classic Mac OS (version 9 and earlier). | | 1989 / 2012 | 214 games |
| Machine Code | Not even assembly computer language was used for these games. The programmer wrote raw machine code. | | 1976 / 1978 | 2 games |
| Maemo OS | Maemo is a Linux distro based on Debian GNU/Linux and GNOME. It uses the Hildon application framework (GTK-based) and the Matchbox window manager. | | 1988 / 2003 | 3 games |
| Mandriva Linux (Mandrake Linux) | Originally Redhat based. Uses rpm. Know for Windows-to-Linux migration tools, urpmi package manager, & nspluginwrapper allowing 32bit plugins on 64bit | | 1993 / 2009 | 71 games |
| Map generator (Random map generator;Procedural map generator)[level generator] | Uses (random) map/level generator to create most or all areas where the player can go to instead of shipping with regular human designed static levels or maps. | | 1981 / 2012 | 177 games |
| MecaniQue Interactive Fiction Authoring System | Proprietary IF creation software by Gabor de Mooij | | | 1 games |
| MechWarrior 2 game engine | Uses MechWarrior 2's game engine. | | 1995 / 1998 | 11 games |
| Microprose Adventure Development System (M.A.D.S.) | | | 1992 / 1994 | 3 games |
| Microsoft Windows | | | | 0 games |
| Middleware(Libraries;Engines) | | | | 0 games |
| Minix operating system | Originally intended as a learning tool to understand how UNIX-like OSes work. Minix 3 & later, however, are also intended to be of practical use. | | | 5 games |
| MiNT OS (FreeMiNT OS) | Game runs on MiNT operating system. The opensource OS that Atari adopted for the Falcon. Later renamed FreeMiNT. | | | 1 games |
| Minux operating system | Originally intended as a learning tool to understand how UNIX-like OSes work. Minux 3 & later, however, are also intended to be of practical use. | | | 0 games |
| MorphOS/Quark | An operating system for PowerPC based hardware. Designed for maximum compatibility with all Amiga applications. | | 2004 / 2005 | 4 games |
| MPlayer.com (Mplay;MPlayer) | Multiplayer service that ran from 1996 till 2001. | | 1997 / 2000 | 5 games |
| MT Framework engine | A game engine by Capcom specifically developed for Dead Rising, Lost Planet and possibly a third game. | | 2006 / 2010 | 12 games |
| Multics OS (Multiplexed Information and Computing Service OS) | Games for Multics operating system. Ran from 1964 till October 31, 2000. Very influential on UNIX. | | | 1 games |
| Nazghul Game Engine | Used to create Ultima V or earlier style RPGs. Relies [i]heavily[/i] on TinySCHEME scripting to construct content and define its interaction. | | 2003 / 2006 | 2 games |
| ncurses | Is a free software foundation version of curses, which is a library for implementing GUI & graphic looking applications using only text display. | | 1986 / 2011 | 14 games |
| Nebula Device 3D game engine | An open-source game engine by Radon Labs. | | 2005 / 2008 | 2 games |
| NetBSD operating system | Games for NetBSD. A freely redistributable version of BSD. | | 1982 / 2012 | 29 games |
| Networking middleware(Networking libraries)[Network libraries] | | | | 0 games |
| NeWS (Network extensible Window System) | Originally the "SunDew project. NeWS is windowing system by Sun Microsystems | | | 1 games |
| Nintendo eShop | Online service for the Nintendo 3DS. It features a cash-based system instead of the points based system used with the Wii and Nintendo DSi. | | | 0 games |
| Nixstaller | Nixstaller is an Open Source project with the goal to create user friendly and flexible installers that work on various UNIX like systems. | | 2007 / 2009 | 4 games |
| No Digital Rights Managment | These games notably to not include any Digital Rights Maliciousness despite that they may be expected to. Such as Wii, Android or Windows games. | | 1983 / 2012 | 108 games |
| No DOSBox support | This is temporary tag for any DOS games that are not fully supported in latest DOSBox (not counting regressions). | | 1991 / 1997 | 8 games |
| No install required (Runs off the media;Zero install) | Runs without installing any game files to permanent media besides possible configuration files and game saves. | | 1995 / 1996 | 2 games |
| No saves | Player has no permanent game progress saves of any kind. | | 1980 / 2010 | 48 games |
| Non-game | Entries in UVL that aren't games. | | 1979 / 2009 | 30 games |
| nProtect GameGuard | Anti-hack software. | | 1996 / 2007 | 16 games |
| Objective-C programming language | "Objective-C is a reflective, object-oriented programming language which adds Smalltalk-style messaging to the C programming language." - Wikipedia | | 1994 / 2011 | 6 games |
| OBSOLETE: IBM OS/2 operating system (OS/2 Warp) | OS/2 games. Created for the PS/2 line of PCs by MS and IBM. | | | 378 games |
| OBSOLETE: Text and graphics | Flag the games as `text´ and `raster´ or whatever else they use instead. | | | 0 games |
| Odyssey game engine | Game uses the Odyssey Engine. | | 2003 / 2005 | 5 games |
| Official Hamster Republic Role Playing Game Construction Engine | James Paige, Brian Fisher, and team's retro RPG engine for creating games in the style of SNES/NES/GBA Final Fantasy series. | | 1998 / 2008 | 2 games |
| Offset engine | A game engine by Offset Software. | | | 3 games |
| Onyx engine | Game engine developed by Ubisoft. | | | 4 games |
| Open-source | Tags for open-source software. | | | 0 games |
| Open2x operating system | Fully open-source alternative operating system for the GP2X game console. | | | 1 games |
| OpenAL (OAL;Open Audio Library) | Cross-platform audio API for multichannel 3D positional audio originally by Loki Software. | | 1999 / 2012 | 358 games |
| OpenBSD operating system | Games for OpenBSD. Fully Open Source & documented fork of NetBSD. | | 1982 / 2012 | 31 games |
| OpenCV (Open Source Computer Vision) | A computer vision library originally by Intel. | | 2009 / 2011 | 3 games |
| OpenGL (Open Graphics Library;OGL) | Uses or can use OGL for graphics. OpenGL is a cross-platform, cross-languge API for 2D and 3D graphics originally developed by Silicon Graphics, now developed and maintained by Khronos Group. | | 1983 / 2012 | 873 games |
| OpenGL Utility Toolkit | Game uses GLUT library or any alternative implementations of the GLUT API. | | 1999 / 2007 | 11 games |
| OpenVMS operating system | Games for OpenVMS. | | 1983 / 1996 | 4 games |
| Operating system limit | Games that have artificial limiter that prevents them from being played on operating systems they fail to recognize or think are unable to run the game properly. | | 1994 / 2007 | 4 games |
| Outdated technology | Any and all tags that refer to software technology that is no longer in use because something has replaced them, and thus may give troubles when trying to play games with them. Excluding operating systems/platforms. | | | 0 games |
| Panzer General engine | | | 1994 / 1997 | 10 games |
| Pardus Linux | | | | 1 games |
| Pascal programming language | Games written in Pascal, an imperative and procedural programming language, developed in 1970 by Niklaus Wirth. | | 1981 / 2006 | 33 games |
| PCLinuxOS | Linux from Texas. A Debian derived distro with influences from Mandriva. Also from Gentoo, OpenSuSE, Fedora, & Ubuntu. Backed by the PCLinuxOS company | | 2005 / 2009 | 7 games |
| Performance issues (Speed issues) | The game is for a system that has no variation in hardware yet still runs into occasional performance issues. | | 1990 / 2003 | 4 games |
| PhenoProtect copy protection | | | | 1 games |
| PHP (PHP Hypertext Preprocessor) | An alternative to Perl that allows servers to execute C like code. A few games have been programmed using it. These nearly always require a server. | | 2004 / 2011 | 5 games |
| Physics middleware (Physics engines;Physics libraries) | | | | 0 games |
| Pixel doubling (Pixel multiplication) | Optionally multiplies the size of each individual pixel. An accessibility feature for those whose hardware can't deal with the original resolution or who wants to play windowed and the original resolution is too small to be actually playable. | | | 0 games |
| PLD Linux | A Linux distro for advanced users focused on system administration for a wide variety of architectures. | | 1998 / 2008 | 6 games |
| PopCap Games Framework | Primarily 2D game engine from PopCap Games. | | | 1 games |
| Predefined controls (Single predefined control layout) | Offers only single configuration of controls with no options to change the button layout or anything else. | | 1994 / 2012 | 27 games |
| Prism3D engine | Game engine by SCS Software. | | 2001 / 2005 | 6 games |
| Programming languages (Scripting languages;Computer languages) | | | | 0 games |
| Programming libraries | Any programming libraries that are not better described by the various middleware groups. Usually general purpose programming aids or too behind-the-scenes elements to not be noticeable to end user. | | | 0 games |
| PunkBuster anti-cheat software | | | 1999 / 2009 | 23 games |
| PureBasic programming language | A programming language based on established BASIC rules. | | 2005 / 2009 | 3 games |
| pygame | A game development framework that wraps SDL for Python. | | 2001 / 2010 | 94 games |
| Python programming language | | | 1995 / 2011 | 158 games |
| Qnx operating system | QNX/Q-nix is a POSIX compliant, unix-like operating system.
| | 1994 / 2003 | 4 games |
| QSound (QSound3D) | Uses QSound Labs' cross-platform audio API. | | 1992 / 2001 | 48 games |
| Qt (cute;cutie) | A cross-platform development framework. | | 2006 / 2009 | 3 games |
| Quake engine (Quake 1 engine) | Uses Quake's game engine. | | 1996 / 2009 | 22 games |
| Quantum3 engine | A game engine by High Voltage Software. | | 2008 / 2009 | 3 games |
| Quarterdeck Desqview/X | A system for running UNIX/X11 applications in an MS-DOS or compatible environment. | | | 1 games |
| Quesa 3D | An open source alternative to Apple's QuickDraw™ 3D API that adds some features. | | | 2 games |
| QuickBasic (QBASIC) | Unlike BASIC, QBASIC is a compilable structured programming language. Though supported, line numbers & GOTO are discouraged in favor of subroutines & functions | | 2000 / 2004 | 24 games |
| RAVE (Rendering Acceleration Virtual Engine) | Apple's short-lived cross-platform rendering API. | | 1997 / 2001 | 4 games |
| ReactOS | Games that run on ReactOS, an alternative OS that aims for 100% Windows compatibility and is opensource. | | 1991 / 2005 | 20 games |
| REALbasic computer programming lanuage and IDE | "REALbasic is a rapid application development environment that enables developers to create high-quality, native software for Windows, Mac and Linux"
| | | 3 games |
| REDCODE | Abstract assembly language 1st used [i]within[/i] Core Wars (UNIX) on a virtual machine in the game known as a Memory Array Redcode Simulator(MARS) | | 1983 / 1999 | 2 games |
| Redhat Linux OS | Games that run on Red Hat. A commercial Linux distro. Red Hat, Inc.'s best known product. Includes [b]7 years of support[/b]. [gametag=fedora]Fedora[/gametag] is the free version. | | 1979 / 2010 | 53 games |
| Redhat Package Manager (RPM) | Comes in a RPM package. Other distros beside Redhat/Fedora can use theses packages also. | | 1986 / 2011 | 89 games |
| Refractor 2 game engine | A game engine by Refraction Games and Digital Illusions. | | 2002 / 2009 | 8 games |
| RenderWare engine | A 3D graphics engine by Criterion Software. | | 2001 / 2012 | 44 games |
| RISC OS operating system | Famous for fewest & least harmful viruses of any OS & no spyware ever. | | 1989 / 2005 | 10 games |
| Rockstar Advanced Game Engine | | | 2006 / 2009 | 8 games |
| RSTS-11 or RSTS/E operating system | A multi-user time-sharing OS by DEC for the PDP-11. Maintained from 1970 until 1992-09. | | | 1 games |
| Ruby language | Coded and/or extensible in Ruby, a programming language designed by Yukihiro Matsumoto. | | | 4 games |
| S3 Texture Compression (S3TC;DXTn;DXTC;GL_EXT_texture_compression_s3tc;GL_EXT_texture_compression_dxt1) | A group of lossy texture compression algorithms originally by S3 Graphics included in DirectX 6.0, OpenGL 1.3, and subsequent versions. | | 2004 / 2011 | 6 games |
| SAGA engine | | | 1994 / 2009 | 9 games |
| Saves stored on removable storage | Game saves and such are saved on removable storage media, such as a floppy disk or memory card. | | | 0 games |
| SCI11 - Sierra's Creative Interpreter Version 1.1 | Created with Sierra's Creative Interpreter Version 1.1, an adventure game engine. | | 1992 / 1994 | 8 games |
| SciTech SNAP (SciTech System Neutral Access Protocol;OpenSNAP) | A dynamically loadable device driver architecture. | | | 10 games |
| SCO UNIX (SCO OpenServer;SCO Open Desktop;Xenix) | A closed source UNIX maintained by the SCO Group since 1989. Originally a bare bones OS for OEMs to customize, the server and desktop were later added | | 1983 / 1995 | 3 games |
| SCUMM (Script Creation Utility for Maniac Mansion) | A scripting engine used by many LucasArts games. | | 1987 / 2003 | 27 games |
| SecuROM PA | SecuROM's internet activation based copy protection. | | 2006 / 2011 | 23 games |
| SecuROM v4 copy protection (SecuROM New) | Copy protection scheme.
Game only runs if a drive knows the difference between a read-only & writable disk. Many read-only drives do not. | | 2001 / 2003 | 5 games |
| SecuROM v4.7-4.83 copy protection | Copy protection scheme | | 2001 / 2003 | 3 games |
| SecuROM v4.84+ copy protection | Copy protection scheme.
This version adds to v4.7 the ability for a game to check a disk to verify the copy protection is present on it. | | 2002 / 2003 | 2 games |
| SecuROM v5 | A copy protection scheme. | | 2004 / 2005 | 7 games |
| SecuROM v7.x copy protection | Copy protection scheme. | | 2004 / 2010 | 83 games |
| Self Modifying | Games that can alter their own programming. | | | 1 games |
| Serial key (Product key;CD-key;Serial number;Unlock key;Registration key) | Requires some form of alphanumeric key or similar to be presented to prove you own an authentic copy. A weak copy-protection mechanism, but more useful as GUID which it is also used for. | | 1998 / 2012 | 223 games |
| SEUK (Shoot'em Up Construction Kit) | | | | 1 games |
| Sierra's Creative Interpreter | Uses any version of SCI, a game engine that is basically only a scripting language and a runtime environment. Used primarily for adventure games. | | 1988 / 1995 | 37 games |
| Silent Storm engine | Game engine developed by Nival Interactive | | 2003 / 2010 | 9 games |
| Simple DirectMedia Layer (SDL) | A cross-platform multimedia library designed to provide low level access to audio, keyboard, mouse, joystick, 3D hardware via OpenGL, and 2D video framebuffer. | | 1986 / 2012 | 1053 games |
| Single save | Offers only single save slot per player, character, storage device, etc. | | 1985 / 2011 | 76 games |
| Sith engine | Game engine developed by LucasArts. | | 1997 / 2000 | 4 games |
| SkyOS operating system | proprietary | | | 1 games |
| Slackware Linux Distro (Absolute Linux) | | | 1999 / 2009 | 24 games |
| Slax Linux Distro | Designed to be installed on thumbdrive, Media card, MP3 player, iPod, digital camera, etc & ran from any computer the device will interface with. | | | 1 games |
| Slayer game engine | A game engine developed by The Collective. | | 2002 / 2006 | 12 games |
| SLUDGE engine | And adventure came oriented engine and associated development tools. | | 2008 / 2010 | 8 games |
| SmartE copy protection (SmarteSECURE) | A copy protection scheme. | | 2005 / 2006 | 4 games |
| Social network service(Community service) | Includes internal social network service(s), allowing at the very least easy communication with friends (even outside of games). | | 2006 / 2011 | 36 games |
| Soft Solid 3-D engine | | | 1983 / 1984 | 3 games |
| Solaris operating system (IllumOS;OpenSolaris) | | | 1979 / 2011 | 68 games |
| Sonic Robo Blast 2 Engine | A variant of the GPLed Doom engine, allows side & 3rd person cameras, cut-scenes, and many 3D platformer elements. | | | 0 games |
| Source code included | For non-FOSS games that provide their source code, usually through some very restrictive license. | | 1979 / 2007 | 17 games |
| Source engine | Uses Valve's Source engine that was developed with Half-Life 2. | | 2004 / 2012 | 60 games |
| Speech synthesis (Text-to-speech;TTS)[text to speech] | Features speech synthesizer in one capacity or another. | | 1981 / 2011 | 28 games |
| Spring engine | | | 2007 / 2009 | 7 games |
| SQLite | A tiny C library to embed a tiny SQL database engine into a program without any fuss.
| | | 2 games |
| Starbreeze engine | A cross-platform game engine by Starbreeze Studios. | | 2004 / 2007 | 4 games |
| StarForce copy protection | A copy protection scheme that has garnered perhaps the most criticism when compared to other mechanisms (barring things like Steam).
Installs low-level system drivers to perform their task. | | 1998 / 2010 | 58 games |
| SunOS operating system | | | 1989 / 2005 | 26 games |
| Supaplex Engine (Megaplex Engine) | | | 1998 / 2004 | 2 games |
| Super Pitfall Engine | A game engine by Steve Bjork used famously for Super Pitfall & less so for Mine Rescue. | | 1986 / 1988 | 3 games |
| Super Simple Texture Compression (S2TC;SSTC;S2 Texture Compression) | Uses S2TC, an Open alternative to S3TC. Almost as good quality a lot faster and patent free. | | | 0 games |
| SUSE Linux (SUSE) | | | 1979 / 2012 | 74 games |
| SVGALib | | | 1997 / 1998 | 3 games |
| Syllable OS | | | 1999 / 2006 | 2 games |
| Text Adventure Development System | A shareware, later freeware, interactive fiction programming system by High Energy Software. Comes in TADS 1, 2, 3, & Multimedia TADS versions. | | 1992 / 2004 | 17 games |
| The Wonderful World of Eamon | Uses the Eamon text plus graphics game engine to play the 240+ games created for it. | | | 3 games |
| TheEngine | A 3D engine by SkyFallen. | | 2005 / 2009 | 9 games |
| Theora video encoding | Uses Theora video encoding format by Xiph.Org, often stored in Ogg container format. | | 2007 / 2011 | 11 games |
| Titan game engine | Uses the Titan game engine created by Stainless Steel Studios. | | 2001 / 2006 | 6 games |
| Tops-10 operating system | [b]T[/b]imesharing/[b]T[/b]otal [b]OP[/b]erating [b]S[/b]ystem. Designed 1964 for the PDP-10. It is still commercially available or usable at no cost under Hobbyist License. | | | 1 games |
| TOPS-20 operating system | The 2nd proprietary OS for the DEC PDP-10. It was the most popular proprietary OS for that system. It replaced TOPS-10 (the 1st). | | | 1 games |
| Torque Network Library | These development libraries are optimized for gaming and designed to overcome high packet latency, limited bandwidth and packet loss. | | | 0 games |
| Tracker music (Sequencer music;Module music;MOD music) | Music is in some tracker/module format. | | 1995 / 2000 | 8 games |
| Tru64 UNIX (DEC OSF/1;DEC-UNIX) | A UNIX Built on the Mach kernel. Originally by DEC (OSF/1), it is currently owned by Hewlett Packard. | | | 3 games |
| TUTOR programming language | A [[tag:plato PLATO system]] language for creating computerized 'lessons'. Quickly rescued from obscurity when numerous games were created for it. | | | 2 games |
| TUTOR programming language (PLATO Author Language) | Developed for [gametag=plato]PLATO[/gametag]. Purely designed for teaching, it was unintentionally used for games. | | 1975 / 1977 | 2 games |
| TuxCap Framework | A non-proprietary alternative to PopCap Framwork | | 2007 / 2008 | 2 games |
| Ubuntu Linux (Kubuntu;Xubuntu;Edubuntu;Gobuntu) | Comes with/Installs very simply on Ubuntu. | | 1976 / 2012 | 834 games |
| Ubuntu Software Center - Paid for Application | These games can be purchased using the Ubuntu Software Center "paid" category. | | 2001 / 2012 | 27 games |
| Unbound speed (CPU bound speed) | Game speed is purely dependent on how fast your computer can run it, making them run unplayably fast on newer machines without artificial means of slowing it down. | | 1989 / 1998 | 4 games |
| UNIX operating system | Originally by AT&T Bell Labs. Various branches & version (with their own groups/platforms) were made over the years including BSD, OSX, & SunOS. Trademark is now owned by The Open Group. | | 1971 / 2005 | 25 games |
| Unreal Engine 2 (Unreal Engine 2X;Unreal Engine 2.5) | Second generation Unreal Engine by Epic Games. | | 2001 / 2010 | 91 games |
| Unreal Engine 2X | | | | 0 games |
| Vicious Engine | A game engine (middleware) by [[company:Vicious Cycle Software]]. | | 2005 / 2009 | 11 games |
| Virtools Web Player | Allows interactive programs to be embedded in web pages or playable in a browser. Similar is some ways to Macromedia Flash. | | | 1 games |
| Virtual Theatre game engine | A cross-platform adventure game engine by Revolution Software designed to run on Windows, DOS, Atari ST, Amiga, Macintosh and Playstation. | | 1992 / 2003 | 11 games |
| Visual Basic programming language | Version of BASIC that is object-oriented & event-driven. Events, functions & subroutines are associated with GUI elements by default. | | 1995 / 2008 | 9 games |
| VLOS Linux (VidaLinux Desktop OS) | A Gentoo based distro designed for ease of use (unlike Gentoo). | | | 1 games |
| Vorbis audio encoding | Uses Vorbis audio encoding format by Xiph.Org, often stored in Ogg container format. | | 1999 / 2012 | 311 games |
| Voxel Space engine | Uses any generation of the Voxel Space engine, created by NovaLogic. | | 1992 / 2000 | 10 games |
| WeiNGINE | A 3D to 2D pre-rendered RPG game engine by Planewalker Games. | | | 1 games |
| Win3.x compatible | | | | 0 games |
| Win32s | Uses a subset of the Win32 API that allows it to be run in 16 bit O/S, such as Win3.1. | | | 1 games |
| Windowed only | Runs only in a window. | | 1988 / 2010 | 37 games |
| Windows 2000 (Win2K;Windows NT 5.0) | Runs natively on Win2k and is supported by the developers/publishers on it. | | 1997 / 2011 | 345 games |
| Windows 95 (Win95) | Runs natively on Win95 and is supported by the developers/publishers on it. | | 1994 / 2009 | 190 games |
| Windows 98 (Windows 98SE;Windows ME;Windows Millenium Edition) | Runs natively on Win98 and/or WinME and is supported by the developers/publishers on it. | | 1995 / 2009 | 284 games |
| Windows NT4 (WinNT;WinNT4;Windows NT 4.0) | Runs natively on WinNT4 and is supported by the developers/publishers on it. | | 1995 / 2009 | 38 games |
| Windows Phone 7 Operating System | | | 2010 / 2011 | 2 games |
| Windows Vista (Windows NT 6.0) | Runs natively on Vista and is supported by the developers/publishers on it. | | 2002 / 2012 | 369 games |
| Windows XP (WinXP;Windows NT 5.1;Windows NT 5.2) | Runs natively on WinXP and is supported by the developers/publishers on it. | | 1998 / 2012 | 622 games |
| Windows: 16 bit installer | Installer is 16 bit application even if the game itself is 32 bit. Prevents installation on 64 bit Windows as the 16 bit sub-system is missing. | | 1995 / 1999 | 9 games |
| WinG API | A predecessor to DirectX designed primarily to aid porting DOS games to 16-bit Windows. Early version of 32-Bit Windows also supported it. | | | 0 games |
| wxWidgets[wxWindows] | Cross-platform widget toolkit for building GUIs. | | 2006 / 2011 | 24 games |
| X Window System (X11) | Requires X11, such as XFree86, X.org or Xming. | | 1986 / 2010 | 153 games |
| X-Ray Engine | | | 2007 / 2009 | 3 games |
| X86-16 | Requires x86 CPU and an OS that can run 16 bit executables. | | 1993 / 2000 | 7 games |
| XFree86 X11 sever for GP2X | These game require the GP2X11 server to run. | | | 1 games |
| xTrap anti-cheat software | Uses xTrap to protect against cheaters. | | 2004 / 2009 | 4 games |
| Zeeboids | Zeeboids is an application, the videogame Zeebo, to create custom avatars, which can be used in games that have supported the application. | | | 0 games |
| Zeta OS | ZetaOS was a continuation of BeOS based at least partially on sourcecode from the never officially released BeOS R5.1. Some game only run on Zeta OS. | | 2001 / 2009 | 34 games |
