MakeIndex is a tool used to add an index to a LaTeX document. To create such an index, you should

  1. Add the command "\usepackage{makeidx}" to the top of the source file
  2. Put a "\makeindex" command in the document preamble
  3. Put a "\printindex" command where the index should appear, often just before "\end{document}"
  4. Put index references in the source document, as in the example below:
"There are many animals in the world\index{animal}. Examples include bears\index{animal!bear}
and tigers\index{animal!tiger} and various insects\index{insect|see{animal}}."

To create the index, typeset the document as usual. Then run MakeIndex. Then typeset again.

Many additional details can be found in The LaTeX Companion by Goossens, Mittelbach, and Samarin.

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MakeIndex