Crab stitch was one of the first decorative, single row edgings I learned. It creates a rope like edge by working backwards (from left to right). I recently learned a stitch called the twisted single crochet, which creates a very similar edge, but working forwards.
Crab Stitch (Reverse Single Crochet)
The instructions are simple – single crochet in each stitch, working from left to right. Actually doing it can be a bit awkward. For the first stitch, just make a single crochet as you normally would.
Yarn over and pull up a loop like you normally would for a single crochet.
Twisted Single Crochet
Twisted single crochet gives you the same twist in the loops, but working forwards instead of backwards. I learned this technique fairly recently, from Moogly. This one is harder to show in pictures, so I have included both a photo and video tutorial.
Start as you normally would for a single crochet – insert hook, yarn over, draw up a loop.
Now twist your entire hook around completely one time, so the two loops on your hook twist around each other.
Yarn over and pull through both loops to finish your single crochet as normal.
Here’s how it looks after a few more stitches:
Video Tutorial (no sound):
The two edges are very similar, though not quite the same. Depending on where your working yarn is when you start an edging, sometimes it might be easier to work backwards in a crab stitch, and sometimes it might be easier to work forwards in a twisted single crochet.