Add-ons are optional computer hardware or software modules that supplement or enhance the original unit they are adding on to. Also known as plugins, extensions, snap-ins, or various other vendor-specific names, these modules often have proprietary interfaces that are tightly held by the company that manufactured the original unit in order to prevent competing companies from producing add-ons.
For example, a network switch may ship with an unoccupied but non-standard port to accommodate various optional physical layer connectors, while games and productivity applications often use plug-in architectures which allow original and third-party publishers to add functionality. Web browsers use plug-ins to enable the presentation of new content formats without modifying the underlying web browser.
Manufacturers can use add-ons can to create vendor lock-in by limiting upgrade options to only those available from or endorsed by the original manufacturer. IBM's Micro Channel architecture, technically superior to Industry Standard Architecture as a way to add components to IBM PCs, largely failed to gain wide support due to the difficulty in getting certification for third-party devices.
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Absolute Gamer's Files Archive - Quake - Contains add-ons, skins, levels, upgrades, and total conversions.
Meta Description: [ Various addons for Quake, Quake 2, Quake 3 Arena, Unreal and other games: skins, levels, upgrades, total conversions, etc. ]
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Hack and Slash - Quake TC featuring furious 3rd-person POV hand to hand action, plug-in player models, and intelligent controls.
IKQ QuakeC Mods - Downloadable QuakeC modifications: new weapons, turrets and different missiles.
Minako Quake - Anime mod with new weapons, Q3A style status bar and other extras.
Meta Description: [ Planet Quake is the epicenter for news on all Quake games, especially the upcoming Quake Wars. If you love
the Quake 1, 2, 3, 4, or 5 engine - we have the latest reviews, guides
and more ]
Nehahra Project - Free download Single player expansion pack featuring 3 new episodes and 20 new Quake maps.
Meta Description: [ Total conversion for Quake ]
Our Thing - Downloadable sound pak featuring 65 new sounds for deathmatch play.
Meta Description: [ An easy-to-install Quake add-on that replaces the standard sounds
with kickass ones. ]
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PlanetQuake hosted mods - Includes deathmatch, single player and teamplay modifications.
Meta Description: [ Planet Quake is the epicenter for news on all Quake games, especially the upcoming Quake Wars. If you love
the Quake 1, 2, 3, 4, or 5 engine - we have the latest reviews, guides
and more ]
Quake Matrix - Includes downloads and information about a Matrix modification.
Meta Description: [ Quake Matrix brings all the action and characters from the movie, 'The Matrix', into a total conversion for Quake 1. ]
Quake Reloaded - A Shockwave version.
Meta Description: [ QUAKE Reloaded : a ShockWave online demo of Quake 1 (by Necromanthus) ]
Rocketland - Includes news, maps, skins and information on the rocketland mod.
Rune Central - The official website for Rune based QuakeC modifications for ID Software's Quake.
Rune Quake - A QuakeC Modification for Quake and Quakeworld.
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