File: groff.info,  Node: Language Concepts,  Next: Command Reference,  Prev: gtroff_Output.php">gtroff Output,  Up: gtroff_Output.php">gtroff Output

6.1.1 Language Concepts
-----------------------

The fundamental operation of the GNU 'troff' formatter is the
translation of the 'groff' input language into a device-independent form
primarily concerned with what has to be written or drawn at specific
positions on the output device.  This language is simple and imperative.
In the following discussion, the term "command" always refers to this
intermediate output language, and never to the 'groff' language intended
for direct use by document authors.  Intermediate output commands
comprise several categories: glyph output; font, color, and text size
selection; motion of the printing position; page advancement; drawing of
geometric objects; and device control commands, a catch-all for
operations not easily classified as any of the foregoing, such as
directives to start and stop output, identify the intended output
device, or place URL hyperlinks in supported output formats.

* Menu:

* Separation::
* Argument Units::
* Document Parts::