Garry's Mod logo
|Release date(s)||December, 2005 (original release)
November 29, 2006 (Steam release)
|Genre(s)||Nonlinear Physics game, RPG|
|System requirements||1.7 GHz processor, 512 MB RAM, DirectX 8 compatible videocard (DirectX 7 is technically supported, but many visuals are lacking), Windows 2000/XP/Vista/7, internet connection, Source engine game (with Source SDK for Garry's Mod 9)|
|Input methods||Mouse, Keyboard, Joystick|
Garry's Mod requires the user to own one Source engine-based game (games including Source SDK), such as Half-Life 2, or Team Fortress 2, and that the Source game has been used at least once. This ensures that the necessary program files are provided to Garry's Mod. The game can be bought in a pack bundled with other Source games or purchased over Steam.
Garry's Mod was created in 2004 by Garry Newman's Team of Developers. It started out as a mod that allowed users to rope things to go together, and it made the pistol shoot out manhacks and other things to build. Since then, the game has gone through various versions, adding more and more features until it became the game based mod it is today. After the tenth version of Garry's Mod, the mod was no longer referred by its number and just called Garry's Mod.
The current version of Garry's Mod receives regular updates via Valve's Steam service. Garry's Mod has been available for purchase on Steam since November 29, 2006. It is also now referred to as a "game" by Steam itself, rather than a "mod" or an "addon".
Garry's Mod allows players to manipulate props from any Source engine game installed on their computer (or ones created by the community) using the Physics Gun, or Physgun, a blue version of Half-Life 2's Gravity Gun (the same model as the Super Gravity Gun at the end of Half Life 2 as well as some parts of Half-Life 2: Episode One) that allows objects to be picked up from any distance, adjusted in mid-air and frozen in place. A second, multi-purpose gun called the Tool Gun can perform many tasks such as weld objects together or rope them together with ropes or controllable winches, plus hanging lights and lamps, doors and buttons, or whatever the community is able to code it to perform.
On January 15, 2008, Garry's Mod switched from the Half Life 2 engine to the Source 2007 Orange Box Engine. This update, dubbed the 2008 Update, brought new menu systems and more advanced physics simulations to Garry's Mod.
The change to the new engine allowed Garry's Mod to expand, due to the amount of new material and the enhanced graphics brought in with the new engine. The engine change also added support for the Orange Box content, allowing maps and items from any Orange Box game to be used in Garry's Mod (as long as the required games are installed on the user's computer). This update also caused a large number of community-made addons to stop working.
Garry's Mod features a wide range of extensions, commonly called Mods (resulting in a mod of a mod) or Addons. Most of these can be created using Garry's Mod's implementation of the Lua programming language, which allows users to create their own weapons, entities, gamemodes and other modifications.
Garry's Mod has a popular official download website which has literally hundreds of mods available for download.
Garry's Mod's addons are sorted into several different categories:
Game servers for Garry's Mod will (sometimes with a little help) automatically attempt to send any custom content running on them to the client when they connect.  If a file is impractically large to transmit from the server (there is often a limit imposed by the server operator), the server refuses to send it and the user must download the file from the aforementioned website.
These addons and mods range from the amateur to the professional. Professional addons usually include a detailed readme or help file. Other addons include modification or addition to the basic Source files e.g. blood effects, dynamic gibs, prop models, gamemodes etc.
Most Garry's Mod mods are packaged in "addon format", meaning the mod's files are packed into a folder, to allow easier installation. These are then simply placed into the user's "addons" folder. All addons must include a file named "info.txt" which includes general information about the addon, such as the Name, Author and Description. Without this file, the addon will not work. After installing any new addons (in addon format) the game must be restarted.
Users may refrain from installing many addons (especially in addon format) as installing too many can cause overall game instability. Furthermore, having large quantities of addons can drastically increase loading time.
Sometimes popular mods have an Subversion (SVN) where you can get the latest content from the creator, say if there was a bug in the latest release, then it may be fixed in the SVN version. A very popular program used for this is TortoiseSVN.
Wiremod is an addon for Garry's Mod, containing objects and components which can be used to add increased functionality to existing contraptions and objects built within the game. The components range from simple buttons and lamps to expression gates, CPUs, hydraulics and many others. An example of a contraption built using Wiremod would be a smooth elevator (one that does not move so fast the player is thrown about) or a drivable car which does not require use of the numpad. More advanced contraptions like autopiloting aircraft or laser-guided rockets and even fully-functioning computers are also possible, with the player only being limited by his/her knowledge of wire itself. Wire is almost universally accepted as a component of GMod and many established servers have it installed. Some professional builders attack its usage heavily, some stating that much of its functionality can be replicated with stock tools and ingenuity.
The Phoenix-Storms Model Pack (often referred to as simply PHX) is a model pack which includes many geometric objects (such as cylinders, cuboids and plane parts) and other miscellaneous objects to allow more precise building. The PHX pack also includes various material textures.
The appearance of SpaceBuild brought the advent of crude (and some more advanced) space-faring contraptions. To this end, the SpaceBuild Model Pack was created to make building these contraptions easier. The pack included a wide range of modular props designed specially for ship construction. Recently, the creators renamed the addon to SpaceBuild Enhancement Project, adding content like ship weaponry working in concert with Wiremod and GCombat (the latter is another addon that makes certain weapons able to destroy previously unbreakable props). The pack is constantly updated and thus, it is officially designated as a fully working alpha version.
As with any Source mod, a broad variety of maps is also available to download. Some of these maps have a specific intention e.g. ragdoll destruction and mutilation, construction areas, sea battles, space battles with different planets, etc. Some custom-made addons have become a part of Garry's Mod, such as finger poser.
Garry's Mod has a massive scope for modification, and in fact was designed primarily with this as its goal, but due to the amount of modifications available to the player, and the lack of any form of quality control, Garry's Mod sometimes suffers from incompatibility issues. Modifications and maps are made that require certain elements from other source games, or conflict with other mods installed and thus display errors or chequered pink and black textures (the games' method of highlighting ones that are missing). In many cases, the only method of curing an issue, due to the wealth of configurations and thus the scope of potential problems, is to delete all modifications installed and recollect them all, often a lengthy procedure.
Garry's Mod has made use with Subversion clients as a way of installing select, up-to-date addons, notably Wiremod, Spacebuild and PHX.
Garry's Mod is often criticized for its high RAM requirements. This is not a shortcoming in Garry's Mod, as sandbox editors must cache the contents of the map in RAM. Slow gameplay can be avoided by intelligent construction of creations (properly using in-game tools to reduce the amount of physics calculations), and installing more RAM in the user's computer will give an increase in FPS, and reduce in-game lag.
Official minimum RAM requirements are cited as 512MB, though the Garry's Mod community often recommends at least 2GB for optimal performance.
Facepunch Studios is the official forum for Garry's Mod. It has forums dedicated to the discussion of mods, maps, Lua scripting, construction, along with other Garry's Mod and non-Garry's Mod related discussion.
The highly-changeable nature of Garry's Mod allows for different game types in different servers. Among the most popular are: