INTRODUCTION LaTeX is typesetting software that is widely used by mathematicians and physicists because it is so good at typesetting equations. It is also completely programmable, so it can be configured to produce documents with almost any desired formatting, and to automatically number equations, figures, endnotes, and so on. To prepare manuscripts for the American Journal of Physics (AJP), you should use the REVTeX 4.1 format for Physical Review B preprints, as indicated in the documentclass line at the top of this article’s source file. (If you’re already familiar with LaTeX and have used other LaTeX formats, please resist the temptation to use them, or to otherwise override REVTeX’s formatting conventions, in manuscripts that you prepare for AJP.) This sample article is intended as a tutorial, template, and reference for AJP authors, illustrating most of the LaTeX and REVTeX features that authors will need. For a more comprehensive introduction to LaTeX, numerous books and online references are available. Documentation for the REVTeX package can be found on the APS web site. LaTeX is free software, available for Unix/Linux, Mac OS X, and Windows operating systems. For downloading and installation instructions, follow the links from the LaTeX web site. It is most convenient to install a “complete TeX distribution,” which will include LaTeX, the underlying TeX engine, macro packages such as REVTeX, a large collection of fonts, and GUI tools for editing and viewing your documents. To test your installation, try to process this sample article.