.NET Framework Version 4.0  4.5
- A highly compatible, in-place update to the .NET Framework 4.
- By using together with the C#, Visual Basic, or F# programming language, you can write Windows apps.
- Includes significant language and framework enhancements for C#, Visual Basic, and F# (so that you can more easily write asynchronous code), the blending of control flow in synchronous code, a responsive UI, and web app scalability .
- Adds substantial improvements to other functional areas such as ASP.NET, Managed Extensibility Framework, Windows Communication Foundation, Windows Workflow Foundation, and Windows Identity Foundation.
- Delivers better performance, reliability, and security.