The handbooks are multi-page "books". 

Book Navigation

You can wind up on a page within a book in a number of ways like using the site search feature or clicking on a menu link like the Handbook menu items. 

All handbooks include a navigation block at the top and bottom of each page. 

Clicking the Table of Contents button will display a list of pages at the current level. There will be a list of subsections/child pages at the bottom of a page. If there is no list then the page is a leaf page. 

You can move to the next or prior pages at the same level or up to a higher level page. The movement icons will be enabled if they can be used. The Up arrow icon will be disabled if you are viewing the top page within a book. 

The printer icon allows printing of a subset of pages starting with the current one. 

Bookmarks

The bookmark section provides more details about bookmarking a page. This is a way to save a reference to a page like you can in a browser except that the bookmark is saved on this site. These are private bookmarks.