This section is an effort to give you a feeling for 'How are Web documents organized?'. Usually, there is a start page called home page. This page presents a logo, or a title image, and usually a selection menu in either text or graphical form.
Depending on the document, the structure of the document varies. It might be organized like a photo album, where all pages are on the same level of importance and build a flat hierarchy of pages.
Other documents are more hierarchical. Readers can navigate into subdocuments or higher levels of detail, and thus navigating deeper 'into' the hierarchy in contrast to moving along a level.
Figure 4 on page 
shows a small example of a Web document plan (or hierarchy plan or however
one wants to name it).
Figure 4: A document hierarchy diagram