.NET Framework 4.5
The .NET Framework 4.5 documentation includes information for the .NET Framework 4.5.1, which is released with Visual Studio 2013 and included in Windows 8.1. For a list of new features and changes in the .NET Framework 4.5.1, see what's new. For a list of supported platforms, see .NET Framework System Requirements.
The .NET Framework is a development platform for building apps for Windows, Windows Phone, Windows Server, and Microsoft Azure. It consists of the common language runtime (CLR) and the .NET Framework class library, which includes classes, interfaces, and value types that support an extensive range of technologies. The .NET Framework provides a managed execution environment, simplified development and deployment, and integration with a variety of programming languages, including Visual Basic and Visual C#.
For a list of .NET Framework core technologies and app platform support, see the roadmap. For a general introduction to the .NET Framework for both users and developers, see Getting Started. For an introduction to the architecture and key features of the .NET Framework, see the overview.
The documentation for the .NET Framework includes an extensive class library reference, conceptual overviews, step-by-step procedures, and information about samples, compilers, and command-line tools. To locate the information that interests you, see the following list of main topic areas.