Match the knot to the job, not the other way around
Every knot on this list trades off some combination of strength, ease of untying, and how well it handles a shifting or changing load. A square knot's main appeal is speed and simplicity for a low-stakes job, while a bowline's appeal is holding firm and still being untieable after real load — using one where the other is needed is the most common knot-related mistake.
When it actually matters to get it right
For anything load-bearing where a failure could cause injury, such as climbing, rigging, or towing, use a knot appropriate to that specific activity's established standards and practice it until it is reliable, rather than improvising with a knot learned for a different, lower-stakes purpose.
Frequently Asked Questions
Is the square knot safe for tying down a heavy load?
Not reliably — it is intended for light, steady tension like tying off a bundle. For anything heavier or safety-critical, a knot specifically suited to that load, like a properly rated hitch, is the safer choice.
Why is the bowline sometimes called the "king of knots"?
Because it combines a strong, non-slipping loop with the ability to be untied easily even after being loaded heavily, a combination that few other knots manage as well.