Windows Presentation Foundation

Windows Presentation Foundation (or WPF) is a graphical subsystem by Microsoft for rendering user interfaces in Windows-based applications. WPF, previously known as "Avalon", was initially released as part of .NET Framework 3.0. Rather than relying on the older GDI subsystem, WPF uses DirectX. WPF attempts to provide a consistent programming model for building applications and separates the user interface from business logic. It resembles similar XML-oriented object models, such as those implemented in XUL and SVG.

WPF employs XAML, an XML-based language, to define and link various interface elements. WPF applications can be deployed as standalone desktop programs or hosted as an embedded object in a website. WPF aims to unify a number of common user interface elements, such as 2D/3D rendering, fixed and adaptive documents, typography, vector graphics, runtime animation, and pre-rendered media. These elements can then be linked and manipulated based on various events, user interactions, and data bindings.

WPF runtime libraries are included with all versions of Microsoft Windows since Windows Vista and Windows Server 2008. Users of Windows XP SP2/SP3 and Windows Server 2003 can optionally install the necessary libraries.

Microsoft Silverlight provides functionality that is mostly a subset of WPF to provide embedded web controls comparable to Adobe Flash. 3D runtime rendering has been supported in Silverlight since Silverlight 5.

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