VGM (Video Game Music) is an audio format for multiple video game platforms, such as Sega's Master System, Game Gear, Mega Drive/Genesis, MSX, Neo Geo, PC (Adlib/SoundBlaster), and has expanded to a variety of arcade system boards since its release.
The normal filename extension is .vgm, but files can also be Gzip compressed into .vgz files. Technically, .vgz files should be named .vgm.gz, but because some popular operating systems' file managers cannot handle file name suffixes that themselves contain a period, .vgz is used in order to launch a VGM player (e.g. Winamp with the proper input plugin) and not a data compression program such as WinZip or WinRAR.
On November 20, 2005, VGM 1.50 was officially announced, and a new version of the input plugin released. The new version of the format supported PCM optimization for the Yamaha YM2612 sound chip, which significantly reduces the size of VGM files by avoiding redundancy. The first YM2612 VGM archive, Project 2612, optimized all of its packages soon after.