Take a look at these four knots, which may look similar but are all distinct. Which knot would be hardest to undo if you ...

For example, the reef knot is the strongest knot in existence ... the researchers suggest that objects that aren't rigid - such as rope or string - may be harder for people to reason about.

The Mule Knot (a.k.a releasable knot) is ideal to lock off the rope on the belay plate. There are many occasions in climbing when, belaying from the harness using a device which does not self-arrest ...

And that was turning an age-old romantic promise to literally tie the knot in a thin but very sturdy rope binding their wrists at the Mahakumbh Mela. "The rope is thin, but our bond is strong ...