combine tar and gzip

newcfd

simple command to combine gzip and tar:
  to tar and gzip a dir(for example testdir):
         tar -cvz testdir >> testdir.tgz
  to uncompress it
        tar -xzf testdir.tgz
  you can also do it in two steps:
      gunzip testdir.tgz ==> get testdir.tar
      tar -xvf testdir.tar