Modules can be considered as separate applications. They are used to add missing features like a guestbook or a calendar to Website Baker.
Modules are installed via the WB Backend:
Add-Ons -> Modules -> Install Module.
After the installation, you will find a new entry in the page menue:
Pages -> Add Page -> Type.
Page type modules can be used by adding a new page or section with the new page type.
News-Feeder