I heard there are hardware and software emulations. What type of emulation is the one used on the Xbox 360?
The Xbox 360 will use a combination of both hardware and software emulations. It is a hardware emulation because the hardware architecture has changed dramatically (CPU changed from a x86 to a PowerPC architecture and the GPU changed from DirectX 8 to “well beyond DirectX 9”). It is also a software emulation because Microsoft needs to develop a piece of software that allows the Xbox games to run on a different platform other than the one they were written for. The fact that there is a different architecture and hardware, forces this software emulator to simulate the Xbox hardware, accept the Xbox code, execute the Xbox games, and provide the same performance of the Xbox videogame system. Not only does this software emulate the Xbox CPU and GPU, but also provides the functionality of some other hardware components found on the Xbox that no longer exist in the Xbox 360.