Oftentimes you need to link to an external site, a section or a figure within your book. Use the Create a link button to open up the Link dialog.
Figure 4-5 Adding an external link
Figure 4-6 To link a section within your book, type in name of the section and select it from the results.
Figure 4-7 Look up a figure by its title or description.
Note that the text a section or a figure is linked to gets updated dynamically to its corresponding numbering such as Chapter 3 or Figure 3-1.