2.1 COM, OLE and Automation

Office compound documents are based on the Component Object Model (COM) [5] and the Object Linking and Embedding (OLE) [6] standards, which govern the interactions between the various software components used to create compound documents.

COM enables software components to export well-defined interfaces and interact with one another. In COM, software components implement their services as one or more COM objects. Every object implements one or more interfaces, each of which exports a number of methods. COM components communicate by invoking these methods.

OLE is a set of standard COM interfaces that enable users to create compound document by linking and embedding objects (components) into container applications, hence the name OLE.

Automation is an OLE technology, which enables third party applications to remotely control Office applications. Puppeteer adapts applications, to a large extent, by invoking Automation interfaces to modify application behavior when executing on bandwidth limited platforms. For example, using Automation interfaces, Puppeteer can adapt a large PowerPoint presentation by loading only a couple of slides, instead of the full presentation, before returning control to the user. While the user works on these slides, Puppeteer loads the remaining slides in the background, and as new slides become available, it instructs PowerPoint to append them to the presentation.