To continue this hijack just one more post...
The closeup that Ben posted indeed looks like light webbing (aka grosgrain) used as the edge binding.
That's only one material, however, and typically used where you need a lot of support for the fabric, and the kite can support the extra weight. You can also use .75 oz or 1.5 oz ripstop, folded in half (for 2 layers) or double folded (for 4 layers) over the fabric edge, or simply double roll the edge of the sail itself to create a reinforced hem. They all do the same thing and are appropriate in different sail weights and wind ranges. For your DC (nice!), I'd suggest the ripstop edge binding as the typical treatment.
Now back to our regularly scheduled topic.