The .NET Framework is:
* Common Language Runtime ??? provides an abstraction layer over the operating system
* Base Class Libraries ??? pre-built code for common low-level programming tasks
* Development frameworks and technologies ??? reusable, customizable solutions for larger programming tasks

Every new version of the .NET framework comes with new features, enhancements to core libraries, and some great new libraries. Learn about the improvements in .NET framework 4 including updates to C# and VB.NET, the introduction of MEF, the Dynamic Language Runtime, and parallel programming extensions. We will also cover some of those less glamorous, but highly useful additions to classes and libraries you use every day like System.IO and System.Net.