问题
I read a lot of different opinions on it, but is WinRT an actual desktop OS like Win 7 and 8? Will you be able to run fully featured desktop applications and games?
回答1:
WinRT is not a desktop or an OS, it is an API. Just like the traditional winapi. It is fundamentally different from the winapi, it is COM based instead of C based and it doesn't expose all of the underlying OS capabilities. And runs in a strong sandbox that prevents using the kind of apis that malware likes to use. Roughly, the kind of subset you'd need to run apps on a tablet computer safely and keep a battery going for a while.
You can still run traditional winapi desktop apps on the full version of Windows 8, but not on the upcoming tablet version with an ARM processor. Creating a Metro style app requires using WinRT. There's a language projection available for it in CLR version 4.5 which requires using the ".NET for Metro apps" platform target. It is a heavily trimmed version of the regular .NET Framework, classes and/or methods that are not WinRT compatible are removed. And WinRT specific classes were added, particularly the kind that you use to implement a UI.
回答2:
No, they need to be written in Metro.
回答3:
Windows on ARM processors (Windows RT) will only support applications included with the system (including some Office 15 desktop applications), supplied through Windows Update, or Metro applications acquired through the Windows Store. Windows on ARM will not support running, emulating, or porting existing x86/64 desktop applications to ensure the quality of apps available on ARM
see here
来源：https://stackoverflow.com/questions/11177022/is-winrt-capable-of-running-win-7-and-8-desktop-apps