Win32 and COM APIs
Windows 10 Universal Windows Platform (UWP) apps and Windows 8.x apps can use a subset of the Win32 and COM APIs. This subset of APIs was chosen to support key scenarios for Windows Runtime apps that were not already covered by the Windows Runtime, HTML/CSS, or other supported languages or standards. The Windows App Certification Kit ensures that your app uses only this subset of the Win32 and COM API. In a native app, you can call these APIs directly. In a managed app, you can call them via a Windows Runtime Component. For more information, see the Windows Runtime components documentation.