Note: there are lots of noteworthy sites explaining what I explain here, and they do it even better then me. The intent with which I wrote this page is only to let people visiting my page, and that still do not know or haven't ever heard about it, to be informed at least a little bit about this phenomenon called "emulation".
As the name itself says, an emulator is a program that "emulates" a computer. It is so possible to play games written for, say, a Commodore 64 using a modern PC and a program (named emulator). As emulators are programs they just require enough processing power to run (emulate); as power of modern PC's grows faster and faster you'll probably be amazed how some older hardware (old PC, old consoles, etc.) can revitalize with just some programs. And you'll be even more amazed to know that this hardware isn't that old (see, for example, the Playstation emulator "bleem").
Mame is an emulator and lets you play (under some license rules) to most of this games.
Neo Geo is the name of a famous console. The games developed for this console are the best: SNK is the principal producer for them.
I made this page just to point your attention to the old generation of games ('80): if you loved to play those, then you can find, in some way, more info or even an emulator and games to play with.