A clove hitch is two crossing turns around a rail or post, with the rope trapping itself. It goes on in seconds and can be slid along a rail to adjust, which is why sailors use it for fender lines. It is not a knot to trust alone under a steady sideways pull — back it up with a half hitch when it matters.

“Over, cross, over, tuck.”



Fenders. That is the clove hitch’s day job. You come alongside, the pontoon is higher than you thought, and you need every fender up 20cm — a clove hitch unties, slides and reties faster than anything else. Add a half hitch on top and it will happily sit there all week.
It is also the knot for a quick tie to a rail, a flag halyard, or lashing a boathook down. What it is not is a mooring knot: for a ring or a bollard use a round turn and two half hitches.
For light, constant-direction loads, yes. It can roll and work loose if the pull changes direction or the line is stiff and slippery. Adding one or two half hitches around the standing part makes it genuinely secure.
A clove hitch is tied around an object; two half hitches are tied around the rope’s own standing part after a turn. Practically: clove hitch for fenders and quick ties, round turn and two half hitches for mooring to a ring.
Yes — form two loops, lay the second behind the first and drop them both over the post. That version is much quicker than threading the end, and it is what most sailors do when the post has a free top.
Loosen the tucked end and unwind the two turns. It rarely jams, even after being loaded, because the turns do not cinch down on each other the way an overhand-based knot does.
Reading a knot and tying it on a pitching foredeck are different skills. Test the first one in two minutes, then close the gap with the course.