Garry's Mod (commonly abbreviated as GMod), is a sandbox physics game created by Garry Newman, and developed by his company, Facepunch Studios. Garry's Mod was originally a mod for Valve Corporation's Half-Life 2, but was later made into a standalone release in 2006 for Microsoft Windows, published by Valve Corporation. Later updates saw an OS X port added in 2010, and a version for Linux in 2013.
Although Garry's Mod is listed as a full game, the base gamemode 'sandbox', has no set objectives and instead gives the player the freedom to manipulate ragdolls or props such as furniture, shipping containers and dumpsters.
Props and ragdolls can be selected and placed into the sandbox from any installed Source engine game or from community created collections, such as PHX3 for props and Civil Protection model packs for ragdolls. An important tool offered to the player, the Physics Gun allows for props and ragdolls to be picked up, rotated, and frozen in place. Another important implement, the Tool Gun is a multi-purpose tool for performing various tasks, such as constraining props together, creating interactive buttons, and creating controllable winches and wheels. It can also be used to change the facial expression and pose the digits of a ragdoll. The Tool Gun can also be used to control and use add-ons created by the community, which can be only accessed through the Steam Workshop.
The game uses the Source engine's modified version of the Havok Physics Engine, which allows players to build contraptions that follow the laws of physics, allowing for very real simulations of structures and experiments.
Garry's Mod allows users to take advantage of the extensibility of the Source Engine through the spawn menu which enables users to spawn models and maps imported by the user. Since Garry's Mod version 9, Lua scripting has been a notable feature added to the game which allows players to run their own scripts, which expanded potential user modifications by enabling the creation of scripted weapons, entities, vehicles, tools, gamemodes and NPCs that weren't possible in the game before. Multiplayer game servers will automatically attempt to send any custom content to the client when they connect. Most users prefer to download the Server Data from the Steam Workshop. Popular mods include Trouble in Terrorist Town, DarkRP, Deathrun, Jailbreak and Prop Hunt.
Wiremod is a user-created mod that significantly expands the sandbox capabilities of the game by adding a large number of pseudo-electronic components such as microcontrollers, logic gates, buttons, radios, gyroscopes, screens, GPS modules, sensors, laser rangefinders, speed sensors and much more. Wiring these components together allows the player to create a very large variety of electronically-controlled machines. It also features Expression2 (E2) general-purpose controllers, which allow the player to program the chip with a high-level programming language to compute inputs and outputs to control a wide swathe of elements. CPU modules, which use a Low-level programming language, allow similar capabilities, as well as the capability to render graphics on a digital screen, to be able to fully simulate a virtual computer. The use of Wiremod allows the creation of very complex contraptions, and everything from virtual computers to missiles, aircraft, spaceships and space probes, robots and drones; all constructed from components available in-game without the use of modded entities.
In winter 2009-2010, a contest was held for Garry's Mod by the game's developers to create the best new game mode using a programming framework called "Fretta". Fretta, Italian for "hurry", allows developers to quickly and easily create new game modes for Garry's Mod with commonly required functionality already implemented so the developers can focus on unique aspects of their game modes. Fretta was inspired by a similar fan-created framework "Rambo_6's Simple Gamemode Base". However, for inclusion in Garry's Mod, Newman decided to rewrite it with input and contributions from the original author and other developers. The winners of the contest range from a recreation of the Mafia party game to an aerial combat game mode. The contest winners have been included in Garry's Mod with their own Steam Achievements.
Three of the winning games have been shipped, Trouble in Terrorist Town, Dogfight Arcade Assault, and Prop Hunt.
Garry's Mod 12 added a function called Toybox into the spawn menu (in Sandbox) that allowed players to share and download user-created content. After 2012's release of the Steam Workshop feature, Garry's Mod 13 replaced the Toybox feature with Steam Workshop. With the Steam Workshop feature came more addons for gamemodes other than Sandbox, with nearly 1,000,000 Steam Workshop items. A deeper connection to dedicated servers using "collections" (a feature called FastDL for its faster download speeds than downloading directly from the server itself), and other small improvements.
Garry's Mod became available on Valve's digital distribution service Steam on November 29, 2006. In the past, playing Garry's Mod was free from 2004 to 2005, with the last free version released on November 27, 2005. As of September 2014, the game had sold over 6 million copies. As of January 2016, the game has sold 10 million copies.
In September 2015, a sequel based on Garry's Mod has been confirmed and is now under development. Attention surrounding the Garry's Mod sequel took off when Newman took to Facepunch Forums asking users what they could change. From the thread, confirmed changes/features include a new hook system for addons, sandboxed addons, permissions to access local hardware on the player's PC, in-game Workshop browsing/spawning, and Lua modules.
However, in March 2016, creator Garry Newman revealed that there had been little progression on the planned sequel and suggested it "might never come out."
On August 15, 2016, Newman was asked on Twitter for the actual date in which he replied: "sept 16th".