Whipstitch is a stitching technique which involves making small up and down stitches to securely fasten two material pieces together. This approach provides resilience and
stops the fabric from fraying. The join together is used for a variety of stitching projects, including hemming, sewing appliques, or even making quilts. It gives a clean and expert look for the final piece.
How to Whipstitch with Pictures wikiHow