3.4 | 12 Votes
What is a GM file?
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.
Programs that open or reference GM files
Transport Tycoon Music File
1.5 | 2 Votes
MIDI files are also used by OpenTTD, the open source follow-on version of Transport Tycoon, but OpenTTD uses the ".mid" extension for game music instead of the ".gm" extension.
NOTE: GM files are also used by the Win32 version of Transport Tycoon Deluxe (TTD), the successor to Transport Tycoon.