File Extension NES
File extension NES is used by Nintendo Entertainment System ROM images, which contain the same data as stored on original video game cartridges. This allows gamers to play console titles on the PC or Mac using emulation software.
Emulation software first began to appear around the mid 1990's, when it became possible to mimic the behaviour of various consoles using entirely software-based applications. However, console manufacturers released few technical details of their products, and so emulators were built using reverse engineering of software which ran on platforms such as the Nintendo Entertainment System. These projects were unofficial, and so were typically carried out by amateur software developers, and as such early emulation software was buggy and support was limited.
Things improved significantly with the release of NESticle, a Nintendo emulator developed by Bloodlust software and released in 1997 on both DOS and Windows platforms. NESticle supported almost all NES ROM images, allowing users to play most games originally released on the Nintendo, and coupled with its ease of use, proved to be very popular. NES files became more common as gamers sought to build or acquire ROM dumping devices which could then be used to create game images for use with emulation software.
Developments on some NES file compatible emulators exist, though there has always been a debate over the legality of reverse engineering software to run on different platforms. This has led to many websites which offered large numbers of NES images - often referred to as ROM dumps - for free to be shut down following complaints from console manufacturers.
NES files can be read by Nintendo Entertainment System emulation software, such as VirtuaNES, FakeNES, Nestopia and FCE Ultra on Windows, or RockNES, iNES or Nestopia on the Mac. There are also a number of Nintendo emulators for UNIX-based operating systems, such as iNES, Nestopia and Mednafen.