There are a lot of knots that are potentially useful for rope sports such as canyoning, climbing, abseiling and caving. However, you are generally better off knowing a small number of knots, but knowing them well. You should know what the knots are useful for, and more importantly, what their limitations are. The knots below are sufficient for just about any situation - most of them have been chosen for having certain attributes, some of which are more important than strength or security. The ones in bold you should learn as soon as possible.

Note that any knot in a rope weakens it. Make sure that you allow for this weakening when choosing the strength of the rope that you are using.

Stopper knots

Stopper knots are used to prevent a rope running through something.

A figure-of-eight tied in each end of the abseiling rope will prevent you abseiling off the end of the rope. Overhand knots (including double overhand knots) are often used to back up other knots, and to tie off loose ends.

Hitches

Hitches are used to tie a rope to something (other than another rope) or around something.

The girth hitch is a very simple hitch that can be used to tie a length of cord or sling to just about anything.

Various friction hitches are also useful in canyoning. For a self belay above the descender, a klemheist or prusik knot should be used. Casual observation indicates that the klemheist is easier to tie, set and release after tension than the prusik knot. However, the standard prusik knot is symmetrical, so can be used regardless of the direction of pull. The French prusik can be used as a self belay below the descender, but can be moved while weighted, so should not be used above.

The Munter hitch is a self reversing knot that can be used to descend with a single carabiner, if your other descenders have been compromised.

The clove hitch is useful in climbing anchors as it locks when tightened, but is easily adjustable.

Bends

A bend is any knot used to join two ropes together.

The double fishermans knot is strong and effective for joining two ropes together. It has the disadvantages that it is difficult to undo after loading, and it has the propensity to catch on edges. The one-sided overhand (overhand EDK) is less strong (although still sufficient) but is much better at passing over sharp edges. Do not use the one-sided figure-of-eight to join two ropes. It is shown only as a warning of what to avoid. The tape knot is used to join two ends of tape together.

Loops

The figure-of-eight (on a bight or rethreaded) is generally the best loop to use, as long as the direction of pull on the tails is opposite to that of the loop. The overhand loop is adequate for this situation as well, although weaker than the figure-of-eight. If the pull on the tails is perpendicular (as in a mid-line loop) then the alpine butterfly should be used.