One of the ways that users find information is by looking up keywords in the index. The index consists of a collection of keywords that are referenced by topics. From the Index tab, users see the list of keywords. When they select one and click Display, the topic that references the keyword opens.
There are several ways to use keywords to build an index. Your index can consist of a simple one-level list of alphabetically sorted keywords or it can include a hierarchy of keywords that link to topics, Web sites, email addresses and other destinations. You can also work with keywords that are saved in an index file (.HHK) and you can save keywords in individual HTML files.