Garry's Mod, or GMod for short, is a "sandbox" mod for the first-person shooter computer game Half-Life 2. It was created by Garry Newman, Binaryrifle, Darkinox
The current version of Garry's Mod is version 13, which still receives regular updates via Steam. An older, unsupported version, 9.0.4, is available as a free download at download.com among other places. It requires at least one Source engine game in the user's account to play, and therefore is offered in a reduced-price bundle with Counter-Strike: Source or Team Fortress 2 for those who do not meet that criterion.