The files in this directory plus /usr/man/man0/caa constitute the set of nroff/troff macros described in tmac.name(VII). Mmcruch converts ?pwbmm.src into ?pwbmm.m, ?pwbmm.mcs, and ?pwbmm.mtoc. Vmcrunch makes vmc from vmca. In both cases, the input to ?mcrunch is meant for humans, while the output is meant for nroff or troff, as appropriate. As for /usr/man/man0/caa, orgcmacs, and uommacs, they are either small enough, or used seldom enough so that we don't feel guilty about making nroff and troff read the people-oriented version.