On a Web site or intranet each of the alphabetically arranged entries or subentries is hyperlinked to the page or to an anchor within a page to where the topic is discussed. Since an alphabetical index can be quite long, it is often divided into pages for each letter of the alphabet. Typically, each letter is linked at the top of the page allow a jump to the start of that letter’s section of the index.
One of our favorite cliches is that you can't use the printed book as a model for online information. Web-based information, which is following the same evolutionary progress as online help systems, has inherited this 'books are bad' philosophy. However, any statement we've begun to take for granted bears some re-examination, because unquestioningly accepting dogma undermines our efforts to improve communication.