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1.                 From The Free On-line Dictionary of Computing (19 January 2023):
                   
   
   
                   
                     
   Stuffit
   sit
      <tool, file format> (filename extension: .sit) A file
      archiving and compression utility, developed by Aladdin
    Systems, Inc..  Stuffit was originally developed for the
      Macintosh and is still the Mac standard tool for compression
      and archiving (compressing multiple files into one).  Stuffit
      is now also available for Microsoft Windows and Linux.
      Compared to the standard Windows tool, WinZip, it is faster
      and gives better compression.
      Stuffit archives can be extracted with Stuffit Expander.
      Stuffit Home (http://stuffit.com/).
      (2003-09-20)