Slip stitch

The slip stitch (abbreviated "sl st" or "ss") is probably the easiest stitch, but not one you will be using a lot. The stitch is very flat, but also rigid. It is useful as a final stitch because of its flatness.

To make a slip stitch, you insert the crochet needle through the stitch loops, pick up the yarn (yarn over needle) and pull through the stitch loop and the loop you already had on the needle. Done.