ActiveX extends beyond the ability to interact with standard AutoCAD objects.
The ActiveX support functions that are loaded with vl-load-com allow you to access objects from other applications that support ActiveX. For example, you can open a Microsoft® Word document, retrieve text data from an AutoCAD drawing, and copy the text into the Word document. Or you might access cells in a Microsoft Excel spreadsheet and use the data with your AutoCAD drawing.
When you want to interact with other ActiveX applications, you will need to refer to the documentation for those applications to learn the application's object names and how to work with its methods and properties. Typically, the online Help for an ActiveX-enabled application contains information on its ActiveX interface.