Garry's Mod (stylized as garry's mod) is a sandbox physics game using a modified Source engine, created by Garry Newman. Garry's Mod was originally a modification, a "mod", for Valve's Half-Life 2, but was later made into a standalone game.

Although Garry's Mod is listed as a full game, it has no objectives and instead gives the player a sandbox to manipulate items free of restrictions, although some multiplayer servers use role-play or other game modes created by players. Garry's Mod allows players to manipulate items, furniture and "props" – various objects that players can place in-game. Props can be selected from any installed Source engine game or from a community created collection. The game features two "guns", the Physics Gun and Tool Gun, for manipulating objects. The Physics Gun allows objects to be picked up, adjusted, and frozen in place. The Tool Gun is a multi-purpose tool for performing various tasks, such as combining props, attaching them via ropes, and creating controllable winches and wheels. The Tool Gun is also used to control add-ons created by the community. Garry has shown on YouTube that the player can use Kinect on ragdolls..

Garry's Mod (Premium) provides you with access to 33 - 100 tick allowing you to run faster - more responsive servers.