If you are just starting your emulation journey, do not chase the latest MAME version. Do not worry about CHD files or Laserdisc captures. Find the , audit it with CLRMAME Pro, drop it into RetroArch, and enjoy the golden age of arcades.
For a technical breakdown of why 2003 is still used despite being 'tragic' in accuracy compared to modern MAME, see the threads on ArcadeControls Rebuilding and Cleaning Sets Pleasuredome Reference Set Guide mame 2003 reference romset
A is a specific collection of these individual ROM files packaged together (usually in a .zip archive) to run a specific game. If you are just starting your emulation journey,
The "parent" game has all the main files, while "clone" versions (like a Japanese regional variant) only contain the differences. To play a clone, you must also have the parent zip in the same folder. For a technical breakdown of why 2003 is