The Multiple Arcade Machine Emulator (MAME) requires BIOS files to run certain games. These files are dumps of the Read-Only Memory (ROM) used by certain companies to run their games.
Games made by certain manufacturers, such as SNK (Neo-Geo), Sega (MegaTech, MegaPlay and ST-V Titan) and Nintendo (Playchoice-10) require a separate BIOS file to run. The BIOS files are used for booting and running these games and run the menu code for multi-game systems. They are usually archived in a .zip file which is placed inside MAME's "ROMS" folder along with the game files. The .zip file must be named correctly for the program to recognize it.