From Pathfinder Wiki
Use: The Stevedore knot is a stopper knot, often tied near the end of a rope. It is more bulky and less prone to jamming than the closely related figure-eight knot. This knot is excellent for anchoring a tarp. Pass the end of the rope through a tarp's grommet, tie a stevedore, and anchor the other end with a taut-line hitch. Its added bulk prevents it from pulling through the grommet.
How to tie: