The Windows Runtime API (WinRT) replaces the old Win32 libraries for accessing operating system functions. The WinRT API is object oriented, largely asynchronous, and callable easily by a wide variety of programming languages. Win32 continues to be supported by Windows 8, and it is what enables all existing Windows 7 applications to function in the Windows 8 desktop environment. The following figure shows how existing technologies map to the Windows 8 development platform.
Windows 8 Development Strategy
When considering the impact of Windows 8 on future software development, the following broad strategies should be evaluated:
1- Continue to use existing technologies, and run the application in the desktop environment.
2- Create a WinRT/Metro style smart client application that takes full advantage of the new WinRT and Windows 8 features.
3- Create a browser-based web application that relies on no plug-ins, so it can run in the browser in both the WinRT and desktop environments.
In summary, the new WinRT API and Metro style applications may represent the future of smart client development on the Windows operating system. Existing applications will continue to run in the Windows 8 desktop environment. Additionally, existing web applications that avoid the use of plug-ins will run in the WinRT web browser.