What Does Windows Runtime Library (WinRT) Mean?

In the context of the Windows 8 operating system (OS), the Windows Runtime Library (WinRT) is the default application programming interface (API) used by the OS. It does not replace the Win32 API that has been running underneath all Windows applications, but rather augments it. WinRT is a C++ object-oriented API sitting at the same level as the Win32 API, not a shell that sits under Win32.

Techopedia Explains Windows Runtime Library (WinRT)

  • All the parts of the API are designed to be asynchronous.
  • The API is sandboxed and designed for the easy creation of self-contained or app store-ready applications.
  • It exposes the WPF/Silverlight XAML UI model to developers.
  • The API definitions are in a metadata format, which is the same as the one used for .NET (ECMA 335).
  • It wraps both the Win32 API and the new UI system together.
  • It has a simple programming model for creating UIs. It is especially tailored for Windows developers who do not need to learn the Win32 API or terms like LPARAM or WndProc.
  • The Silverlight/WPF XAML UI model is exposed to developers.
  • It implements the look of Windows (formerly known as Metro)