Whippings are put on the end of a rope to prevent the rope from unlaying. Whippings are most necessary for natural fibre ropes that can't be melted.
Whippings are preferable to back-splices whenever there is a need for the rope's end to pass through an eye or a block. I think a whipping is always preferable because a back-splice will catch on anything at the most inconvenient moment.
Whippings are usually made from waxed twine or rope yarn. For my example I've used some braided cord. A boot lace will do.
The length of a whipping should be at least equal to the diameter of the rope, and for permanent whippings, a second one should be made nine diameters from the end.
My favourite whipping is the sailmaker's whipping. I think it looks great and I've never seen one work adrift. Here's how to make one...