This is a concept which has become very popular in the last 5 or 6 years. For those of you who are completely unfamiliar with emulation, here's a brief explanation.
WHAT IS AN EMULATOR?
An emulator is a piece of hardware or software which performs the functions of an alien system's hardware. In this case, the functions of an arcade game's hardware are emulated in software which then runs on another machine, for which it is written.
HOW DOES IT WORK?
The ROM images that the emulator utilizes are "dumped" from arcade games' original circuit-board ROM chips. The emulator becomes the "hardware" for the games, taking the place of their original CPUs and support chips. Therefore, the games emulated are NOT simulations, but the actual, original games that appeared in arcades.
WHAT'S THE PURPOSE OF ARCADE EMULATION?
The purpose is to preserve the early decades of video-game history. As gaming technology continues to rush forward, arcade emulation prevents these important "vintage" games from being lost and forgotten.
WHAT ARCADE EMULATORS ARE AVAILABLE?
stands for Multiple Arcade Machine Emulator. When used
in conjunction with a game's data files (ROMs), MAME will
more or less faithfully reproduce that game on a PC. MAME
can currently emulate over 1500 classic arcade video games
from the '70s and '80s.