I've put together a few diagrams to help people visualise the who articles, section, categories, menus, modules thing in Joomla.

www.theartofjoomla.com/joomla-structure-pdf.html

It's a version 1 but hopefully it's helpful to some of you.

From what I can see of the web version, it looks great, Mate. But then the PDF download link appears momentarily and is hidden. Using FF.

Be a great recourse for me to keep.

Andrew
I CAN see your PDF in FF2 - did you fix it?
Anyway, I like the way you've got the data structure next to the menu, since it's one of the hardest concepts for new users to get - how the menu structure and the data structure relate to one another. I find it a challenge to explain!
tx

Haven't touched it If you have any other ideas for diagrams that would help you as an implementer, or help you to pass on to clients to help them "get it", let me know.

I recently found this simple table outlaying the ACL in 1.5 and have already found it very useful when explaining to clients what everyone can do. It's probably a common layout but I had never seen it before!

http://brian.teeman.net/joomla-gps/joomla-15-acl-explained.html