gzip will compress a file and gunzip will decompress it back to the original:

1. Compress a file with gzip:

        $ gzip filename
        $ ls
        filename.gz

2. Extract a gzip compressed file:

        $ gunzip filename.gz
        $ ls
        filename

3. In order to list the properties of a compressed file, use the following command:

        $ gzip -l test.txt.gz
        compressed        uncompressed  ratio uncompressed_name
        35                   6 -33.3% test.txt

4. The gzip command can read a file from stdin and write a compressed file to stdout.

Read data from stdin and output the compressed data to stdout:

         $ cat file | gzip -c > file.gz

The -c option is used to specify output to stdout.

The gzip -c option works well with cpio:

        $ ls * | cpio -o | gzip -c > cpiooutput.gz
        $ zcat cpiooutput.gz | cpio -it

5. We can specify the compression level for gzip using --fast or the --best option to provide low and high compression ratios, respectively.