Script written for GameMonkey Script, a scripting language used for embedding logic into games and other applications; uses syntax similar to the C language and uses concepts similar to the Lua language; can be used for custom software modifications. GameMonkey Script files can be run with the GameMonkey Script engine and edited with any text editor.
The GM file extension is associated with Transport Tycoon computer game, developed by Microprose. A *.gm file is basically just renamed *.mid file that can be played in almost any media player.