<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.
