Groff: The GNU Implementation of troff, by Trent A. Fisher and
Werner Lemberg, is the primary groff manual. You can browse it
interactively with 'info groff'.
groff(1)
offers an overview of the GNU roff system and describes
its front end executable.
groff(7)
details the groff language, including a short but complete
reference of all predefined requests, registers, and
escape sequences.
groff_char(7)
explains the syntax of groff special character escape
sequences, and lists all special characters predefined by
the language.
groff_diff(7)
enumerates the differences between AT&T device-independent
troff and groff.
groff_font(5)
covers the format of groff device and font description
files.
groff_out(5)
describes the format of troff's output.
groff_tmac(5)
includes information about macro files that ship with
groff.
roff(7)
supplies background on roff systems in general, including
pointers to further related documentation.
