Garry's Mod is a sandbox physics game developed by Garry Newman. 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 most multiplayer servers offer original game modes created by players.
Since Garry's Mod version 9, Lua scripting has been a notable feature added to the game which allows players to run their very 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. Popular mods include Trouble in Terrorist Town, DarkRP, Deathrun, Jailbreak, and Prophunt.