PCSX2 is a PlayStation 2 emulator for Windows and Linux, started by the same team that brought you PCSX (a Sony PlayStation 1 emulator).
The PCSX2 project attempts to allow PS2 code to be executed on your computer, thus meaning you can put a PS2 DVD or CD into your computers drive, and boot it up!
The project has been running for a little over four years now, and since it's initial release has grown in compatibility. From initially just being able to run a few public domain demos, it's current state enables many games to boot and actually go in game, such as the 'famous' Final Fantasy X or Devil May Cry 3.
PS2 Emulation is a complex task, far worse than emulating a console from the previous generation (PlayStation1, N64, Saturn), simply due to the CPU power required to get 'playable' speeds from a PS2 game under emulation. Whilst speed can be improved via various 'recompilers' (eeREC and vuREC, Emotion Engine recompiler and Vector Unit CPU recompiler respectively), you will still need the latest and most powerfull machine you can get your hands on to even break the 30 FPS mark.
The PCSX2 project is Open Source (GPL) and keeps an active SVN (SubVersion). We encourage geniune attempts to improve the code, in terms of compatibility, new features, optimisation, and encourage plugin authors to write graphics, sound, cdvd, controller plugins.
All PCSX2 downloads are compressed with 7zip. :