Page Layouts is used to edit and administrate your page layouts, which determine how your page is sectioned up and organized. It is an advanced module, intended for web-designers.
Module Templates is used to modify the template and language files for your system. It is an advanced module, intended for advanced web-designers.
Patterns is used to modify and add patterns, which are blocks of content that can easily be added to any portion by using the pattern tool.
The Site Manager modules are used to edit and administrate the actual content of your pages.
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