In the physical arcade world, a game wasn't just a cartridge or a CD; it was a complex circuit board containing a CPU, memory chips, and sound processors. The was the code burned onto a ROM chip that initialized this hardware, telling the machine how to read its controllers, display video, and access the game data itself.
Do not unzip the individual BIOS files (e.g., neogeo.zip ). MAME is designed to read the contents of these compressed archives directly. Key Files Often Included all mame bios