Concepts of document navigation tools such as Bookmarks and Tables of Contents have been around for centuries. However, they’re often under or misused, so I wanted to go back to the basics here, and talk about what these items really are today, and where they are – and are not – appropriate.

The Table of Contents

This is usually one or more pages, found towards the beginning of the document that provides a quick understanding of the structure of the document: chapters, sections, subjects, etc. Clever use of indentation can elude to the fact that one topic is a part of another, larger subject.

The advantage of a Table of Contents is that it becomes a part of the content; often the table of contents references itself.  This is an advantage because if you were to print a hard copy of this document, you can retain this navigation tool to quickly look up the topic of interest, determine the page number, and then use your fingers to navigate to that page.

PDF Bookmarks

This is the functionality found in most PDF Viewers to display the list of Chapters, Sections, etc. It works as the document structure in a special tool bar or pane, while also viewing the document content. The advantage to this navigation tool is that it goes with you, no matter where you are in the document.

It is by far the best way to navigate between sections of the document, and it also allows you to see where you are in most documents, as your current location will be highlighted (Notice in the image, right, how the Table of Contents item is highlighted with a light grey bar?)

The disadvantage of PDF Bookmarks is that they’re only available when viewing this content in a PDF Viewer that supports it.  While most PDF Viewers will support the display and navigation of PDF Bookmarks, if you were to print the document, or convert it to an alternative format, you lose this navigation tool.

Ultimately it is the delivery vehicle (electronic vs. paper) that will drive which navigation tools to use. It doesn’t make sense to navigate back to the Table of Contents in a document when you’re already in the middle of it, so TOC is not particularly useful if your documents will only be delivered electronically in PDF format. However, if you primarily, or even occasionally, generate hard-copy versions of your documents, the PDF Bookmarks are lost, and the Table of Contents becomes quite important.

Either way PDF, which has become the standard file format for exchanging and archiving documents, provides flexible and convenient options for allowing the consumers of your documents to quickly navigate to the content they are looking for. Rendering platforms, such as Adlib’s, can intelligently generate these navigation tools for you by automatically analyzing the structure of your documents and incorporating that into these powerful navigation tools.