The Code Navigator provides a hierarchical outline of the following in your Project:
The Code Navigator is a virtual representation of your EPUB (and items that are used in the compilation of your EPUB, such as Templates and Extensions). When a Book is exported to EPUB, the hierarchy shown in the Code Navigator will be reflected in the exported EPUB.
Working with Code Navigator
Manipulating the contents of the Code Navigator is easy. Simply drag and drop any custom Resource to another location.
When editing code, you can drag a Resource from the Code Navigator into your code to create a link to the dragged item.