What is COM?

Question

I searched hard, but was unable to grasp the whole idea. Can anyone tell me:

• What COM actually is?
• How do GUIDs work, and how are they used by COM? <

Answer 1

COM is Microsoft's Component Object Model, a binary-compatible interface for programs written in various languages to interoperate with each other. It is the "evolutionary step" between the OLE and .NET technologies.

If you want to learn about COM from the C++ perspective, take a look at Don Box's Essential COM, or ATL Internals by Rector and Sells.

The group microsoft.public.vc.atl is probably the best place to ask questions you can't get answers for here. It's primarily an ATL newsgroup, but it seems to be the newsgroup with the most traffic for general COM questions as well. (just be prepared for the usual newsgroup curtness & impatience)