UDO (markup language)
UDO is a lightweight markup language. It requires the installation of a special UDO "converter program" that can convert UDO documents to Apple-QuickView, ASCII, HTML, Texinfo, Linuxdoc-SGML, Manualpage, Pure-C-Help, Rich Text Format, ST-Guide, LaTeX, Turbo Vision Help or Windows Help formats. UDO is released under the GNU General Public License.