It is a declarative XML-based language that defines objects and their properties in XML. You can create visible UI elements for a Windows Presentation Foundation (WPF) application in the declarative XAML markup, and then separate the UI definition from the run-time logic by using code-behind files, joined to the markup through partial class definitions. It is very intuitive for creating interfaces ranging from prototype to production especially in the sense that a web designer's exact layout can be saved in XAML and combined with the application without affecting the development process. XAML files are XML files that generally have the .xaml extension.
XAML syntax describes objects, properties and their relationships to one another. Generic XAML syntax defines the relationship between objects and children. Properties can be set as attributes or by using 'period notation' to specify the object as a property of its parent.
XAML is a part of .NET 3.0 and is used in writing WPF applications.
The Visual Studio 2008 contains "Cider", the Visual Designer for WPF. The designer's split view editor lets you see your XAML and a design view of it simultaneously, so you can see consequences of your XAML edits immediately without having to run your application.
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