.NET Framework applications are built on the services of the common language runtime and take advantage of the .NET Framework class library. The common language runtime manages memory, thread execution, code execution, code safety verification, compilation, and other system services. The .NET Framework class library is an object-oriented collection of reusable types that tightly integrate with the common language runtime. You can use these types to develop traditional command-line or graphical user interface (GUI) applications, as well as applications based on ASP.NET, Web Forms, and XML Web services. You can develop your .NET Framework applications in Visual Basic, Visual C#, Visual F#, or Visual C++; any of these programming languages can be used equally well.
To download the .NET Framework version 4, use the links provided in Installing the .NET Framework. Detailed information about the .NET Framework appears in another section of the documentation: .NET Framework 4. The following links to key sections are provided for convenience.
Describes key .NET Framework concepts such as the common language runtime, the common type system (CTS), cross-language interoperability, managed execution, assemblies, and security.
Explains common programming tasks that apply to a range of .NET Framework applications: accessing data, file and stream I/O, configuration, encoding, deployment, and debugging.
Provides links to information about developing managed applications for resource-constrained computing devices in Visual Studio 2008. .NET Compact Framework application development is not supported in Visual Studio 2010.
Provides additional reference information for the .NET Framework, including ASP.NET and ClickOnce reference topics, configuration file schema, unmanaged API reference, XML standards reference, and a glossary of terms.