Slip Stitch

This makes a very thick, dense, stiff fabric that can be kind of stretchy.

Basically you just put your hook in the stitch and pull the loop all the way through.

Finished pieces appearance:

Slip stitching through the back loops. I think this makes a nice rib stitch.

Slip stitching through both loops

My Notes, 

See number 6 on right bottom of page for slip stitching into back of rib.

#7 slip stitching into both loops