The Double Figure of Eight Bend. The Figure Eight Knot meaning a figure eight is tied at the end of one rope and then the second rope follows the turns of the first in parallel, but from the opposite direction. When complete, the working ends will exit the knot on opposite sides.
It is much more reliable than the abnormal form which is tied by holding two ropes together and then tying the Figure Eight knot. In the abnormal form, the working ends will exit on the same side.
If tied, dressed and stressed properly, the bend is fairly secure but susceptible to jamming. For additional security, "stopper" or "safety" knots can be added to the tails.