Garry’s Mod is a sandbox physics game developed originally by Garry Newman and later by Facepunch Studios as a modification of Valve’s Half-Life 2. It would ultimately be made into a standalone game for the PC, OS X, and Linux.
In spite of being classified as a full-fledged game, Garry’s Mod has no set objectives but rather gives the player a sandbox to manipulate items in free of any constraints. Garry’s Mod allows players to manipulate items, furniture, and props that the player is ultimately able to place in the game. The Physics Gun allows objects to be picked up, manipulated, and frozen in place while the Tool Gun allows the player to perform a wide range of interactions such as constraining props together, making interactive buttons, or creating controllable winches and wheels as well as control add-ons created by the community.
Gary’s Mod incorporates ragdoll posing of models and allows players to pull Source Engine-based game models into Garry’s Mod and manipulate them using the in-game toolset, making this a popular tool for making fan videos and machinimas. Taking full advantage of the Source Engine’s modified Havok Physics Engine, the user is able to construct complex contraptions, vehicles, structures and more that follow the laws of physics allowing for extremely realistic experiments. Garry’s Mod incorporates several game modes including the open Sandbox, Trouble in Terrorist Town, Jailbreak, and more. With the release of Gary’s Mod 9, Lua scripting was added as a feature to allow players the ability to run their own scripts, vastly expanding the complexity of items, weapons, vehicles, tools, NPC’s and more that a player could create and place into the environment.
Gary’s Mod was originally distributed for free from 2004 to 2005 and then sold on Steam by Valve in 2006. It has sold over six million copies as of 2014.