Possible Duplicate:
How does the new Windows 8 Runtime compare to Silverlight and WPF?
Is it JavaScript, C#, C++, or VB.NET?
Possible Duplicate:
How does the new Windows 8 Runtime compare to Silverlight and WPF?
Is it JavaScript, C#, C++, or VB.NET?
WinRT is implemented in COM, so C++ is the native language. .NET and JavaScript access WinRT through marshalling.
Here is a detailed answer: How does Windows 8 Runtime (WinRT / Windows Store apps / Windows 10 Universal App) compare to Silverlight and WPF?