The bowline I think is the most valuable Knot.
Learn to tie it in frongt of you and behind you, so that you can do it in any situation.
The bowline is a knot that is easily untied by pulling on the bitter end.
It can be used in a line for a quick loop over a cleat, a sliding loop where you tie the bowline and pass the bitter end through it to form a lasseo type effect. Learn to tie one around your waist and if applicable you wife or childrens waist.
The bowline is the most aux. knot I use.
The true Cleat Knot is something that many people just don't understand. It is the most important knot at the dock, unless you are at pilings, then the bowline /lasseo is the #1.
The cleat knot is so often miss tied. I have seen it miss tied on masts, docks, booms, you name it.
I think the third knot is the truckers hitch. If you can't find it, let me know and I will shoot a picture and atempt a discription. I think this is my most used knot because I use it in my working enviorment.
A few others, a figure eight tied through the open portion of the cleat on the mast will keep the halyard from going over the top.
Knots are great, it isn't how many you know, it is that you know how to use what you know.
r.w.landau