Hi. I bought a book on knot tying. There are way too many knots in it.
Unfortunately, I don’t have the memory or the patience to learn and remember a lot of them.
So I would like to know your top 3 knots to learn and why you chose them. Bonus points if they are easy to learn, remember and to untie. Thanks!
For sailing, these are the ones I use most commonly:
Cleat hitch - feebie
Clove hitch - for tying to a piling (no cleat/bollard)
Bowline - tie a sheet(line) to a jib(sail)
Rolling hitch - tie a fender to a life line (with one or two half hitches)
Bonus: Stopper Knot - so lines don’t slip out of a clutch/jammer.
It depends what you want to use them for.
The best knot site on the internet is Animated Knots. It has clear step-by-step animations of hundreds of knots.
Some basic useful knots are:
Hitches (to tie a rope to an object):
Clove hitch, using end and using loops
Round Turn and Two Half Hitches
Loops:
Bowline
Alpine Butterfly Loop
Bends (to join ropes):
Sheet bend
Reef knot
Stopper knots (to prevent a rope untwisting, or pulling through a hole):
Figure 8 (Flemish) Knot
Stevedore knot
It gets easier the more you practice. Each knot you learn will be easier than the last. Have fun! 
Love it. Thanks!
GreenWyvern: Your list is good, except for suggesting the Reef Knot as a bend. Here’s what one expert famously said about that:
One of the reasons it’s so useful as a binding knot (as when reefing a sail) is how easily it can be collapsed - by tugging on one lead.
Are you going to be sailing, or just around the house, or…?
Try the Zeppelin bend for a generic bend (symmetrical therefore easy to learn, secure, and unties easily). (Alternative: Ashley bend)
Magnus/rolling hitch for clotheslines and adjustable loops
Definitely the constrictor knot!! (Opposite if untying easily, but sometimes a permanent binding is what you need)
ETA for a nice big stopper the Oysterman’s stopper is useful
I agree. I was thinking of very basic knots to learn, but you wouldn’t want to put a heavy load on it.
My favorite bend is the Zeppelin Bend, because it’s easy to tie when you’ve got the hang of it, non-jamming, and very secure.
(Ninja’d!)
Repeating the warning about the reef knot. It is absolutely not a bend! Heavy load or not. It is good for reefing and binding, securing your shoelaces, etc.
Taut line hitch is handy. Boy Scouts learn it so they can pitch a tent properly; this is the knot that lets you adjust the overall length of a line/loop manually, and have that length remain unchanged when tension is applied. Not just good for tents - decades later, I use it for bracing plants/trees in the yard, and occasionally for various projects that call for having a loop of rope that can be adjusted to just the right length after it’s been tied.
Other good knots to know are:
Trucker’s Hitch - for stretching a rope tightly between two fixed points
Siberian Hitch - quick release knot, can be tied with gloves on
Gnat Hitch - not well known, but small, easy to tie, secure, and non-jamming
This is a great list. It is missing the reefing knot, better known as a square not.
The Bowline is the best knot in my opinion, I would prioritize it. A knot as strong as the rope itself and yet easy to undo.
Absolutely. Couple of half hitches to make it even more secure and it’s unbeatable under load.
DPRK I am definitely not sailing. I just want to learn (a few) basic, useful knots. I learned the reef knot today and I really like it!
The bowline (for a fixed loop at the end of a line) and the bowline on a bight (fixed loop in the middle of a line) are musts. It’s used in rescues, climbing, or anyplace else that you need a nonslip knot.
A simple square knot is also essential; simple, but if you do it wrong you’ve got what’s called a ‘granny’ knot, which will slip or come undone.
Someone mentioned the sheet bend, which is great for joining two similar or dissimilar diameter ropes together. Again, nonslip if done right.
Ever tie stuff to the top of your car, then play hell keeping it from getting loose? Trucker’s hitch is the way to finish it off.
I’ll go with
It’s a good knot for reefing/binding, just don’t use it as a bend 
I am chiming back in to say that if you are closing up a bag, you can also use a slipped constrictor knot, that way you can get it open by pulling on the slipped end, without having to cut the knot.
In stagehanding, the clove hitch and the bowline are indispensable.
I’m also fond of the trucker’s hitch.
I often also use an Alpine butterfly loop (this one) for that purpose; depends what you need (the bowline-on-a-bight in fact produces two loops).
Excellent video of a better way to tie a Trucker’s Hitch… and a great way to tie a Bowline:
This is my favorite knot that most people don’t know. I’ve used it any number of times for cinching down loads on top of my truck.
My first job out of college was as a field engineer for a steel construction company, mostly in the oil and gas industry. I was on one big job where we would have to lay out piping runs and their concrete supports; a taut piece of string is your friend here. So, one day when I was out with one other young engineer I tied one end of the string to a convenient bolt on a piece of equipment, and then 60 feet away or whatever it was I stuck a welding rod in the ground and tied a tautline hitch. Instant straight line. The guy I was working with acted like he’d just seen a miracle and made me teach him the knot right then and there. 