A text formatting package based on SGML SGMLtools is a text formatting package based on SGML (Standard Generalized Markup Language). SGMLtools allows you to produce LaTeX, HTML, GNU info, LyX, RTF, plain text (via groff), and other format outputs from a single source. SGMLtools is intended for writing technical software documentation. Install sgml-tools if you need a text formatting program that can produce a variety of different formats from a single source file. You should probably also install and try sgml-tools if you're going to write technical software documentation.