What is COM?

Microsoft COM (Component Object Model) technology in the Microsoft Windows-family of Operating Systems enables software components to communicate. COM is used by developers to create re-usable software components, link components together to build applications, and take advantage of Windows services. COM objects can be created with a variety of programming languages. Object-oriented languages, such as C++, provide programming mechanisms that simplify the implementation of COM objects. The family of COM technologies includes COM+, Distributed COM (DCOM) and ActiveX® Controls.

Microsoft provides COM interfaces for many Windows application programming interfaces such as Direct Show, Media Foundation, Packaging API, Windows Animation Manager, Windows Portable Devices, and Microsoft Active Directory (AD).

COM is used in applications such as the Microsoft Office Family of products. For example COM OLE technology allows Word documents to dynamically link to data in Excel spreadsheets and COM Automation allows users to build scripts in their applications to perform repetitive tasks or control one application from another.

Note:

In this project, I will give you all the overview of Microsoft’s COM Technology and various types of COM Dll’s Such as Factory, Containment/Delegation, Aggregation, and Automation. In Automation Dll, you will also see how this Single DLL can be used by Client Applications those are written in different languages such as Python, JavaScript, and .NET.

Check out the Project Source Code for more detailed info on implementation.