MAME
Games
MAWS presents a searchable index of the over 3000 original games (not including clones) that MAME emulates.
NonMAME maintains a list of games not emulated in MAME that are emulated by other projects.
unMAMEd maintains a list of games that have not been emulated in MAME - including many games that are actively being sought out so that their ROMs can be dumped.
Mame Support Files
See also the Screens, Titles & Extras page. Many of those projects overlap.
Cheat
Cheat.dat is useful for both players and developers. Cheating allows players to get past difficult situations and it let's developers test games without having to be good at all the games.
Commands
Commands can be shown either in game or in a front end. Commands allow users to view, among other things, the individual command lists for games. This is especially useful for Fighting Games, but can also show users what individual buttons (and combinations) do without having to press them all. The screenshot is from within MAME Plus!
High Score
Hiscore.dat is a complimentary file to help Mame in saving high scores. Most Mame games save their high scores by default, but over 2500 games do not save their high scores.
The Hiscore.dat file tells Mame some additional information and how to read and store the high scores using the /hi directory instead of /nvram.
