The Microsoft ® Component Object Model (COM) allows applications on Windows-based platforms to communicate and exchange data.
You can access COM interfaces provided by other ObjectARX ® applications or by any COM-enabled application running on Windows.
Additionally, by using COM with ObjectARX, you can augment AutoCAD's ActiveX Automation model. The elements, objects, or entities you expose will be available to other programming environments such as Visual Basic for Applications (VBA), and to AutoCAD ® features such as the Properties palette.