Windows Presentation Foundation, code name Avalon, is a graphical subsystem feature of the .NET Framework 3.0 and comes as a built in package with Microsoft Windows Vista operating system. WPF can also be installed with other popular Windows operating systems like Windows XP SP2 and Windows Server 2003. The objective is to present a steady programming model for applications with isolation between User Interfaces and Business Logic layers. A WPF application is mostly web based but it can also be implemented on a desktop environment. The visual aspects of Windows based programming that expects rich graphics, controls design and development, are well handled by WPF. Many application services like User Interface, fixed documents, adaptive documents, 2D and 3D drawings, animation, audio, video etc. work together in unison under WPF. Microsoft Silverlight that is based on XAML and JScript is a web based subset of WPF. Silverlight helps develop web and mobile applications with codes similar to .NET applications and the applications are similar to Flash.

WPF allows developers to create applications that are friendly and rich in quality to the target users. Developers can use WPF in building applications similar to building applications on Win32 and DHTML based applications and content. Unlike being a typical tool for only developing enhanced graphics, WPF takes care of all forms of presentations like User Interface, media, vector graphics, and documents that can be looked as a novelty in the Windows platform.