Windows Presentation Foundation, a Microsoft graphical system for rendering user interfaces for the .NET 3.0 development framework.
Windows Presentation Foundation (WPF, previously known as “Avalon”) is part of the Microsoft .NET framework used to create rich client user experiences for Windows applications.
It features a diverse set of controls, layout options, 2D & 3D graphics, media & text handling and enables data binding and style-driven templates.
It uses a combination of XAML, an XML-based markup language, and any of the Common Language Runtime languages to define user interface elements. A fundamental aspect of WPF is to separate the user interface definition from the business logic which enables developers and designers to work concurrently on a single project much more easily. WPF also moves UI rendering off to the video hardware through the use of DirectX freeing the CPU to handle more of the logic tasks.