I googled it and found this direction at eHow.com...
It is a hand-sewing stitch.
"Do a backstitch by bringing the needle up from the underside of the fabric and making a short backstitch. Bring the needle up again one stitch ahead. Put the needle in through the end of the first stitch and out a stitch ahead. Repeat as needed. The backstitch is stronger than the running stitch."
The whole article can be found here.