Content Manager works by keeping your content separately from the way it displays. The content (content text, images and files) are stored separately from the items that control the way that content displays (templates, style sheets, and scripts).
The Data Libraries consist of the following:
The Data Libraries contain the data and assets used on the website. Data and assets are stored here and dynamically pulled on to the site's pages as needed. This allows for easy sharing and reuse of site assets.
All of these Libraries have similarities and differences, depending on the type of information contained within them. For example, the Images Library does not use the simple grid list of the other libraries, while the Content List Library does not have the menu tree structure of the other libraries because lists are not associated with a single menu node, but can be inserted anywhere.