набор текста и форматирование документов GNU roff (GNU roff typesetter and document formatter)
Описание (Description)
The GNU version of troff is the heart of the groff document
formatting system. troff is the groff system's formatter, the
program that transforms roff language input into a device-
independent output format. It is functionally compatible with
the AT&T troff typesetter and features numerous extensions. Many
people prefer to use the groff(1) command, a front end which also
runs preprocessors and output drivers in the appropriate order
and with appropriate options.