As stated in the Introduction modules are the smallest parts used in the Ai node-based engine. They are provided by the Ai system. A full list of the available modules is published in the manual which is installed with the software in Distrib\Help\Ai_Man_v8.chm and in the V9 User Manual available at the Avolites Download site.
The modules used in the examples in this wiki are explained here as well so that you can easily link between modules and their use in real-life patches.
Currently these modules are discussed in this wiki: