Topic: RetroDuo NES/SNES system
they play the same game using a different hardware which is considered emulation.
This works the same as a PC with emulators. The rom file is the same file, same code that's stored on the original cartridge. But PC hardware is able to run the game = emulation.
for example if you hooked up a NES cartridge port to your computer and accessed the game file that way, you could play the game right off your original cartridge using an emulator on your PC.