knot

• Trucker’s hitch {Power Cinch Knot, Haymaker’s Hitch, Harvester’s Hitch) has the distinctive feature of providing a mechanical advantage when being tightened. The variety of names for this hitch is a tribute to its widespread use. It is a valuable knot – particularly for securing loads or tarpaulins. (music video)

• Bowline – makes a reasonably secure loop in the end of a piece of rope. It has many uses, e.g., to fasten a mooring line to a ring or a post. Under load, it does not slip or bind. With no load it can be untied easily.

• Square knot (Reef knot – a binding knot and, tied in the right material against a curved surface, the first Half Knot may bind – but it cannot be trusted.

Engineering ideas

• mechanical advantage, tighten, load, slip, bind