Microsoft XAML

XAML stands for Extensible Application Markup Language and is a declarative XML-based markup language developed by Microsoft, used to enhance the development of the visual elements in desktop and web solutions. XAML is created by Microsoft and is used extensively in .NET Framework 3.0 & NET Framework 4.0 technologies, like Windows Presentation Foundation (WPF), Silverlight, Windows Workflow Foundation (WF) and Windows Runtime XAML Framework.

Advantages 

• Provides clear separation of designer code and logic
• XAML code is clean and clear to read, so a professional designer can work with ease on creating the look and feel of the application

Disadvantages

• In ASP.NET it is more rigid than HTML / CSS
• Depends on Microsoft Technology

Development tools

• Expression Blend
• Expression Design
• Visual Studio

Versions

• Windows Presentation Foundation version
• Silverlight 3 version
• Silverlight 4 version
• The Windows 8 XAML/Jupiter version