This data structure inspector was the first use we made of web browsers to provide an interactive interface to a non-trivial running system. In this case we are using the web browser as a window system for an application that knows about how to display data structures within the system in a number of different perspectives. The particular advantage of this approach is that the browser provides a very reliable substrate for an inspector tool. We do not have to be concerned that bugs in the application will crash out the window system.
In this case we have typed in the expression (ol:find-ontology 'ol-user::bibliographic-data) which will cause the inspector to look at the data structure used to encode the ontology called Bibliographic-data. When we click on the button we inspect the ontology in its default perspective.
If you select one of the perspectives in the menu then whatever you choose to inspect will be inspected in that perspective (if applicable). Failing that the best perspective will be selected.