The Free On-line Dictionary of Computing (30 December 2018):

MacBinary

    An eight-bit wide representation of the data and
   resource forks of an Macintosh file and of relevant
   Finder information.  MacBinary files are recognised as
   "special" by several MacIntosh terminal emulators.  These
   emulators, using Kermit or XMODEM or any other file
   transfer protocol, can separate the incoming file into forks
   and appropriately modify the Desktop to display icons,
   types, creation dates, and the like.

   (1995-03-08)