Binary package “groff-base” in ubuntu bionic

GNU troff text-formatting system (base system components)

 This package contains the traditional UN*X text formatting tools
 troff, nroff, tbl, eqn, and pic. These utilities, together with the
 man-db package, are essential for displaying the on-line manual pages.
 .
 groff-base is a stripped-down package containing the necessary components
 to read manual pages in ASCII, Latin-1, and UTF-8, plus the PostScript
 device (groff's default). Users who want a full groff installation, with
 the standard set of devices, fonts, macros, and documentation, should
 install the groff package.