What is XAML?
XAML is a new descriptive programming language developed by Microsoft to write user interfaces for next generation managed applications.
Will XAML Replace C# and VB.NET Languages?
No. XAML complements procedural languages. You can think XAML as ASP.NET. To write ASP.NET applications, you need both ASP.NET and C# (or VB.NET). Similar to ASP.NET, XAML provides user interfaces and C# (or VB.NET) is used as code-behind language.
What is Relationship between XAML and WPF?
WPF is code behind XAML. WPF is a name of .NET API (a set of classes) provide to write user interfaces for XAML under the hood.
What is Relationship between WPF and C# or VB.NET?
WPF is the API similar to Windows Forms or ASP.NET. When you use Windows Forms, you need a languge language such as C# or VB.NET. Similarly, to write WPF applications, you will have to use a language C# or VB.NET.
Will XAML and WPF Replace Windows Forms?
Yes and No. Today, programmers can choose from WPF and Windows Forms. Now Windows Forms will be the older way to write Windows user interfaces and WPF is the new way ;-). It's hard to say how long it will take XAML + WPF model to replace Windows Forms.
Will XAML Replace ASP.NET?
Eventually YES but both Windows Forms and ASP.NET will be supported on Windows Vista and .NET 3.0.
Do I need to compile XAML code?
Yes and No. If you are using any inline code in XAML, then you must have to compile the XAML file, otherwise there is no need to compile XAML.
What do I need to write XAML application?
You need to download .NET 3.0 SDK from MSDN downloads. After installing SDK, you can write your XAML code in a text editor and save code as .xaml and run it by double clicking it. If you are using inline code, then you will have to build the file using MSBuild.