The .NET Framework is an integral part of Windows component. It helps in supporting, building and running desktop applications and Web services. It manages execution environment, simplified development and deployment and supports for a wide array of computer programming languages. There are two major components of the .NET framework which makes it function properly. The components are common language runtime (CLR) which manages memory, code execution and other system services. The other major component is the .NET Framework class library which is a collection of reusable types where you can develop your applications. The .NET Framework also includes other technologies like ADO.NET, ASP.NET, Windows Presentation Foundation (WPF), Windows Communication Foundation (WCF) and Windows Workflow Foundation (WF).
There are various sections in the MDSN library containing documentation of all the versions currently available in .NET Framework. The documentation for each of the versions includes extensive class library reference, conceptual overviews, step by step procedures and code examples.

In order to make it more clear, a brief discussion of each of the versions is required. Starting with .NET Framework 4.5 developer Preview, this contains a number of new features and improvements like .NET for Metro style applications, Windows Presentation Foundation (WPF), Windows Communication Foundation (WCF) and Windows Workflow Foundation (WF). The next is .NET Framework 4 which has the features like application compatibility and deployment, managed extensibility framework, parallel computing, networking, windows communication foundation and windows workflow foundation. Apart from that it also has the optional features in the name of Visual Studio 2010 Service Pack, .NET Framework 4 Platform Update4.0.1 and .NET Framework 4 Platform Update 4.0.2

The .NET Framework version 3.5 is an integral Windows component that supports the building and running next generation applications and web services. The key components of this version of .Net Framework are ADO.NET, ASP.NET, Windows Forms and Windows Presentation Foundation (WPF). The .NET Framework Version 3.5 provides a managed execution environment, simplified development cum deployment and integration with a wide variety of computer programming languages.

The .NET Framework 3 version that released with the Windows SDK for Windows Vista includes .NET Framework 2.0 and added technologies such as WPF, WCF, WF and Windows CardSpace while .NET Framework 4.1 introduces a new productivity API and enables Code First development. It is a technology built to top ADO.NET Entity Framework 4 and it includes the .NET Framework 4.