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Generating an Index
Indexes are automatically assembled from markup you enter in your document. In order to generate an index, the following must be present in the document:
indexterm elements — Each indexterm element generates an entry in the final index. The child elements of indextermprimary, secondary, and tertiary—are combined to produce multiple-level index entries.
index element — Creates an index where this element is located in the document. This element is only inserted into the document once and is left empty. It contains no other elements or content.
The index element must be inserted just inside the book end tag. The index element must be the last thing inside the book element. Do not add content to the index element itself. Leave it empty. Adding content to the index element may produce undesirable formatting results.
Indexes contain both the index entry text and a locator or reference. In a paper index, this reference is usually a page number. In online systems, the locators are hypertext links.