Backstitch is a stitching technique which involves making small in-out stitches with the purpose of
tightly connect two fabric pieces together. This technique gives strength and prevents the material from fraying. The overcast is used for a variety of sewing projects, such as hemming, stitching appliques, or even creating blankets. It offers a neat and professional look to the completed item.
How to Crochet Whip Stitch YouTube