gzip <filename>
# command to compress a file while keeping the original file
gzip -c <filename> > <filename.gz>
# OR
gzip -k <filename>
# command to uncompress a file
gunzip <filename.gz>
# OR
gzip -d <filename.gz>
# OR
zcat <filename.gz>
# -f is used to force compress or decompress
gzip -cf <filename>
# -q supresses all warnings
# -r recursively compresses all the files within a specified directory
gzip -r Documents
# flags to alter the speed and rate of compression
--fast or -1 speeds up the process and results to a lesser compression
--best or -9 is the slowest and give the best compression
-6 is the default
# check out man gzip for more details o compressing several files at once.