.NET Framework: An integral Windows component that supports building, deploying, and running the next generation of applications and Web services.
Metadata: Information that describes every element managed by the common language runtime: an assembly, loadable file, type, method, and so on.
Manifest: An integral part of every assembly that renders the assembly self-describing. The assembly manifest contains the assembly's metadata.
Interoperability : Tools and techniques to interoperate between .NET managed code and unmanaged code include Platform Invoke services and .NET Framework and COM interoperability tools.
Abstract: Abstract classes act as expressions of general concepts from which more specific classes can be derived. You cannot create an object of an abstract class type; however, you can use pointers and references to abstract class types.