gz

gzip
gz

   <tool, compression> {GNU} compression utility.  Gzip reduces
   the size of the named files using {Lempel-Ziv} {LZ77
   compression}.  Whenever possible, each file is replaced by one
   with the {filename extension} ".gz".  Compressed files can be
   restored to their original form using gzip -d or gunzip or
   zcat.

   The Unix "{compress}" utility is patented (by two separate
   patents, in fact) and is thus shunned by the GNU Project since
   it is not {free software}.  They have therefore chosen gzip,
   which is free of any known {software patents} and which tends
   to compress better anyway.  All compressed files in the {GNU}
   {anonymous FTP} area (gnu.org/pub/gnu) are in gzip
   format and their names end in ".gz" (as opposed to
   "compress"-compressed files, which end in ".Z").

   Gzip can uncompress "compress"-compressed files and "pack"
   files (which end in ".z").  The decompression algorithms are
   not patented, only compression is.

   The gzip program is available from any {GNU archive site} in
   {shar}, {tar}, or gzipped tar format (for those who already
   have a prior version of gzip and want faster data
   transmission).  It works on virtually every {Unix} system,
   {MS-DOS}, {OS/2} and {VMS}.