I wish this was a tar tutorial, however there are plenty of them already. Maybe some people find it useful too, specially when downloading, opening tar balls... :)
A ".tar" file is a collection of files within a single file in an uncompressed form. If the file is a ".tar.gz" ( usually called tarball) or ".tgz" file then it is a collection of files in a compressed form.
To compress a file you could create the tar file with the z option. Or alternatively you could create the file with any other tool and then use gzip to compress it.

Some Tar Options

  • c : create a new archive
  • d : delete from the archive
  • r : append files to the end of the archive
  • t : list contents
  • u : update (append files if newer)
  • x : extract
  • f : file?
  • v : verbose
  • z : gzip

Uncomprezing files:

# target file is a zipped tar ball
$ tar -zxvf file.tar.gz
# target file is simply a tar ball
$ tar -xvf file.tar

Listing contents of the file

$ tar -tvf myfile.tar

Compressing files

# tar contents of folder foo in foo.tar
$ tar -cvvf foo.tar foo/
That is all, maybe I add more options as needed.