Very basically it is a braiding technique using plied cords (often 4-ply) which actually go through each other. It is a traditional method for making camel girths, harnesses and similar items in India, but it has evolved into a craft technique that can also be used to create three- dimensional structures like hats, and belts and jewelery. A small tool, not unlike a latch hook for rugmaking, called a Grip Fid, is used to push through the threads in a way that braids a pattern.
The samples on the left are mine, and the other picture shows Caths. I was quite pleased but it won't be a craft that I will pursue, Cath on the other hand was much taken with it and bought supplies to continue at home. The expert was a very nice lady called Julie Hedges.