Texinfo is a documentation markup invented by the Free Software Foundation and used mainly for GNU project documentation — including the documentation for such essential tools as Emacs and the GNU Compiler Collection.
Texinfo was the first markup system specifically designed to support both typeset output on paper and hypertext output for browsing. The hypertext format was not, however, HTML; it was a more primitive variety called ‘info’, originally designed to be browsed from within Emacs. On the print side, Texinfo turns into TeX macros and can go from there to PostScript.
The Texinfo tools can now generate HTML. But they don't do a very good or complete job, and because a lot of Texinfo's markup is at presentation level it is doubtful that they ever will. As of mid-2003, the Free Software Foundation is working on heuristic Texinfo to DocBook translation. Texinfo will probably remain a live format for some time.
