yet another free document preparation system

 This is yet another text formatting system, intended primarily for writing
 software documentation. It accepts a single source format and outputs any
 or all of text, HTML, Windows Help, man pages, GNU info, PostScript, or
 PDF. It has comprehensive indexing and cross-referencing support, and
 generates hyperlinks within output documents wherever possible. It supports
 Unicode, with the ability to fall back to an alternative representation
 when Unicode output is not available.