This document describes some of the behaviour on how different modules (edx, index_ intercommunicate via files, or if you like, messages containing fragments of code: HTML, Javascript and CSS.

This has to happen because edx generates the code for the page, but the index program needs to have access to the icon for each directory so it can make it into the bubble menus.

This is all tied to the thumb-nailing done by upload, index and edx.