How Do You Use the Index in a Book?

To use a book’s index, look up your subject alphabetically, read any smaller entries beneath it, and turn to the listed pages. Follow cross-references when they point you to a different heading. This is especially useful when you need one answer rather than an entire chapter.

Choose the right section

A back-of-book subject index helps you locate particular topics, people, or places discussed throughout a book. It usually appears near the end. A table of contents shows the book’s chapters and larger divisions in reading order; a glossary explains the meanings of selected terms. Southern New Hampshire University’s guide to book sections describes these different jobs.

For example, use the contents to find a chapter about growing vegetables. Use the index to find the pages about watering tomatoes. Use the glossary if you need a definition of a gardening term.

Start with a useful keyword

Reduce your question to its main subject. For “How can I keep herbs growing indoors?”, start with “herbs.” If that produces nothing useful, try “indoor gardening,” “containers,” or the particular plant’s name.

Look under the first letter, then compare the following letters as you would in a dictionary. For a person, try their surname. Multiword entries can be sorted word by word or letter by letter, so scan nearby headings if something seems missing. UCL Press’s indexing guidelines explain both ordering systems.

An unsuccessful first lookup is a reason to try another term, not proof that the subject is absent. A professional index can connect different expressions for the same idea, as the Society of Indexers explains.

Read the whole entry

The main heading names the subject. Subentries narrow it down to particular aspects. They may appear on indented lines or follow the heading in a single paragraph, separated by semicolons. This organization helps you choose a useful passage rather than work through a long string of pages. Hopkins Press discusses these index structures.

Page references are often called locators:

• 24 directs you to page 24.
• 24, 39 gives two separate locations.
• 24–27 points to a discussion spanning pages 24 through 27.
• 124–27 is a shortened way of writing 124 through 127.

UCL’s guidelines distinguish separate mentions from continuous discussions and explain shortened ranges. Check the whole indicated passage, rather than stopping after its opening sentence.

See redirects you to the heading where the information is indexed. See also suggests another relevant heading in addition to the entry you are already reading. UCL Press explains this distinction.

Try this fictional example

The following miniature index was created for this guide. Its imaginary book and page numbers are not references to a published work.

• containers, 10–14
  • choosing sizes, 10–11
  • drainage, 12–13
• herbs
  • indoors, 22–27
  • watering, 24–25
  • See also light
• light, 16–19
  • windows, 17–18
• pots. See containers
• watering, 30–34
  • herbs, 24–25

Suppose you want to know how to water indoor herbs. Find “herbs” under H, then choose the “watering” subentry and turn to pages 24–25. If you also need the surrounding indoor-growing advice, read pages 22–27.

The “See also light” instruction offers additional material on pages 16–19. It does not replace the herb pages. If your next question concerns pots, the P entry sends you to “containers,” where “drainage” points to pages 12–13.

Notice that “herbs” has no page number on its main line. Its subentries supply the locations. Always read below the heading before deciding that an entry is incomplete.

Check special type and digital links

Bold or italic page numbers may identify particular kinds of material, but their meaning varies. Read the note or key at the beginning of the index. For example, University of Michigan Press’s author guide uses italic locators for illustrations and tables; UCL distinguishes figures in italics from tables in bold. Neither convention is a universal rule.

In an ebook, try selecting a linked index locator. Exact-word search can help too, but it does not necessarily gather related concepts or alternative wording as an index does. The Society of Indexers explains why full-text searching and indexes serve different purposes.

Once you reach the passage, read enough surrounding text to check that it answers your actual question. The index gets you to a promising place; the book supplies the explanation.