What is a "tar ball" ?
A "tar ball" is just an archive made with the tar program.
Tar is the usual Linux/Unix archive program -- like zip in the Windows world.
It would typically have suffix (extension) of:
.tar = tar file
.tar.gz = tar file compressed with gzip
.tgz = also a tar file compressed with gzip
.tar.bzip2 = tar file compressed with bzip2
.tar.xz = tar file compressed with xz
Create like this:
tar cfv MYTAR.tar MYDIR
tar cfvz MYTAR.tar.gz MYDIR
tar cfvz MYTAR.tgz MYDIR
tar cfvj MYTAR.tar.bzip2 MYDIR
Extract/Unarchive like this:
tar xfv MYFILE.tar
tar xfvz MYFILE.tar.gz
tar xfvz MYFILE.tgz
tar xfvj MYFILE.tar.bzip2