The Trucker's Hitch
The Trucker's Hitch is useful for binding loads in place typically associated with such tasks for campers as hauling a canoe or other bulky gear on the top of a vehicle or in the bed of a truck or trailer.
It is actually a combination of knots that are used to create a mechanical advantage in tying down the load. It is assumed that there are anchor points such as a rail or eyes which would be at points A and B in the illustration.
A variety of knots can be used to accomplish the task. At point A for instance the attachment of the line can be accomplished with two half hitches or even a bowline loop tied around the anchor point.
The line then proceeds over the load with an inline loop such as the Lineman's Loop (Ashley 1053) at point C. A variety of inline loop knots will serve as well at this point.
The line then proceeds around or through anchor B and back through loop C as illustrated. Pulling on the free end can produce considerable tension in the line. Actually care should be exercised so as not to damage the load in some instances.
Having achieved the desired tension pinch off the line at D to hold the tension.
Work the free end around E in some fashion to secure. This may be two half hitches or even a slipped hitch if quick release is desired.
A closed loop knot that serves a similar purpose can be found as The Tie That Binds on this site.