COM interop, learning ntoes

Dotnet interop (2-way) -- allows COM-based applications to use .NET components, and .NET applications to use COM components

Dotnet wrapers -- Microsoft now focuses much of its marketing efforts on .NET, with .NET providing wrappers to the most commonly used COM controls. However, your own custom COM classes don't have wrappers yet. You can consider COM interop in order to use them in dotnet.

regasm - is needed when your new COM needs an existing dotnet assembly