Microsoft calls their approach emulation, but if you read the details you see they are also translating instructions and caching the result (AOT translating).

Microsoft calls their approach emulation, but if you read the details you see they are also translating instructions and caching the result (AOT translating). https://docs.microsoft.com/en-us/windows/uwp/porting/apps-on-arm-x86-emulation https://docs.microsoft.com/en-us/windows/uwp/porting/apps-on... Their current implementation only supports 32-bit code, x64 translation is still underway. It is not known how well x64 translated code will perform relative to native code.