Aids in the task of checking whether a command defined in a document preamble is actually used somewhere in the document. If you add a statement to use the package cmdtrack to the preamble of your document, all `newcommand' and similar statements between that point and the beginning of the document will be marked for logging. At the end of the document a report of the command usage will be printed in the TeX log, for example: mdash was used on line 25; ndash was never used. The author is Michael J. Downes.