UWP extends the .NET platform allowing you to develop for Windows 10 devices, let it be tablet, PC, phone, HoloLens, Surface Hub, Xbox, or the Windows 10 IoT Core. Extension SDKs can give you specialized APIs for any device class, such as the holographic functionality offered by HoloLens.
It provides a user interface framework that lets you write responsive apps to support all different types of screen sizes and forms of interaction, including touch, game controller, pen, or the simple keyboard and mouse format.