: All versions of a game (parent and clones) are inside a single .zip file. This is the most space-efficient but harder to manage if you only want specific titles. 3. Quick Installation Guide
A set includes every necessary file—both the specific game data and the required BIOS/Parent files—inside a single ZIP file. mame roms zip download
: Keeps the "parent" game and its "clones" (variants) in separate files. You must have the parent .zip for a clone to work. : All versions of a game (parent and