Blood knot

A blood knot is most usefully employed for attaching fishing hooks with slippery monofilament line. The end of the line is passed through the hook hoop, and brought back together with the standing end. Then the hook is rotated about its shank a number of times - at least 5 or 6 times for light line.

Then the running end is passed through the gap left between the now-twisted running and standing ends and the hoop. The knot is pulled tight to appear somewhat like a hangman's knot.