COM Interop is a technology included in the .NET Framework Common Language Runtime (CLR) that enables Component Object Model (COM) objects to interact with .NET objects, and vice versa.
COM Interop aims to provide access to the existing COM components without requiring that the original component be modified. It tries to make the .NET types equivalent to the COM types. In addition, COM Interop allows COM developers to access managed objects as easily as they access other COM objects.