Alternatively referred to as GMod, Garry's Mod is a standalone game available on Steam, a content delivery service created by the company Valve. Garry's Mod allows players to manipulate objects, or "props", in the game, to make creative devices. The game provides players with a Physics Gun and a Tool Gun to manipulate the props and position them wherever they want. Players can also enjoy multiplayer gaming, where they can create devices with another player, communicating with each other via text or voice chat.
Garry's Mod was first made available on Steam on November 29, 2006, but only worked for players who owned Half-Life 2. At that time, Garry's Mod was not a standalone game, but rather a modification. It was later turned into a standalone game and no longer requires players to own another game on Steam. On September 7, 2010, a "Toybox" feature was added for players to utilize the Amazon S3 to download content from third-party sources, including weapons, maps, and props.