A lot of literature on the web teaches the difference between app/design and skin and goes to great length to describe all of their subdirectories and how they relate to each other. However I am struggling with another part of the Magento directory tree. What is the difference in the purpose of the app/code/local and app/etc/modules . While custom code goes in app/code/local is app/etc/modules where the code needs to be declared to actually appear in the admin panel?
Thanks.