x = extract, z = compress/decompress, v = verbose (list files added or extracted), f = filename follows. You can leave off the 'z' if it's a tar without compre

x = extract, z = compress/decompress, v = verbose (list files added or extracted), f = filename follows. You can leave off the 'z' if it's a tar without compression. If it's compressed, the extension is usually tgz, tar.Z, bz2, or something else other than tar. You can leave off the 'v' if you don't want to see a list of which files are being added or extracted.