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Introduction to Gzip

gzip (GNU zip) is a popular data compression program written by Jean-Loup Gailly <> for the GNU project. Mark Adler <> wrote the decompression part.

We developed this program as a replacement for compress because of the UNISYS and IBM patents covering the LZW algorithm used by compress. These patents made it impossible for us to use compress, and we needed a replacement. The superior compression ratio of GZIP is just a bonus.

For versions of GZIP for MSDOS, Windows or the Macintosh, see Gailly's gzip page.

The format of the .gz files generated by gzip is described in RFCs (Request For Comments) 1951 and 1952.

Online Manual is available at

Downloading Gzip

Gzip can be found on in the subdirectory /gnu/gzip/ on your favorite GNU mirror. For other ways to obtain Gzip, please read How to get GNU Software

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Updated: 6 May 2000 neel