Here you go - http://msdn.microsoft.com/en-us/library/windows/apps/hh46494...

From the article: The Windows Runtime is exposed using API metadata (.winmd files). This is the same format used by the .NET framework (Ecma-335). The underlying binary contract makes it easy for you to access the Windows Runtime APIs directly in the development language of your choice. The shape and structure of the Windows Runtime APIs can be understood by both static languages such as C# and dynamic languages such as JavaScript. IntelliSense is available in JavaScript, C#, Visual Basic, and C++.

Edit: Updated the link and added snippet