groff? ¶groff (GNU roff) is a typesetting system that reads plain
text input that includes formatting commands to produce output in
PostScript, PDF, HTML, or other formats, or for display to a terminal.
Formatting commands can be low-level typesetting primitives, macros from
a supplied package, or user-defined macros. All three approaches can be
combined.
A reimplementation and extension of troff and other programs
from AT&T Unix, groff is widely available on
POSIX and other systems owing to its long association with
Unix manuals, including man pages. It and its predecessor have produced
several best-selling software engineering texts. groff can
create typographically sophisticated documents while consuming minimal
system resources.
The architecture of the GNU roff system follows that of other
device-independent roff implementations, comprising
preprocessors, macro packages, output drivers (or “postprocessors”),
and a suite of utilities, with the formatter program troff at
its heart.
The groff front end program makes the GNU roff system
easier to use than traditional roffs that required the
construction of pipelines or use of temporary files to carry a source
document from maintainable form to device-ready output.