Are There Other Choices for Single Source, Multiple Output Markup Languages for Authors?
Yes. Texinfo, the language of the GNU*2* Documentation System, is an example. In the 80’s Texinfo could be used to provide two forms of a GNU document: (1) Info online hypertext, suitable for the text-based terminals with cursor control of that time and (2) finely typeset text in DVI format. By the late 80’s Charles Goldfarb had created SGML, the very general family of markup languages in which HTML is a member and relative to which XML is a subfamily. Although it is formally possible for a language under this umbrella to admit essentially no translation, the intention was to provide powerful languages suitable for multiple outputs and to provide, thanks to the shared syntax, general processing frameworks under which translations can be efficiently and reliably written.
