All contents of the Navigator window are referred to here as "categories," whether headings, sheets, tables, frames, graphics, OLE objects, sections, hyperlinks, references, indexes, comments, or drawing objects.
The Navigator displays types of objects contained in a document. If a plus sign appears next to a category, this indicates that at least one object of this kind exists. If you rest the mouse pointer on the category name, the number of objects is displayed in an extended tip.
Open a category by clicking on the plus sign. If you only want to view the entries in a certain category, select the category and click the Content Navigation View icon. Until you click the icon again, only the objects of this category will be displayed.