S
lip Stitch
A slip stitch is the shortest of all crochet stitches and can be used for a variety of purposes, depending on the pattern. Slip stitches can be used as the last stich on a row to create a smooth end, to join ends in circular crochet, to join in new yarn, or simply to move your hook to a new position.
Step 1:
Put your hook through the next stitch, then yarn over hook (yrh).
Step 2:
Pull yarn through the work AND the original loop at the same time. Your slip stitch is now complete.