A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a hitch fastens a rope to another object; a bend fastens two ends of a rope to each another; a loop knot is any knot creating a loop; and splice denotes any multi-strand knot, including bends and loops. A knot may also refer, in the strictest sense, to a stopper or knob at the end of a rope to keep that end from slipping through a grommet or eye. Knots have excited interest since ancient times for their practical uses, as well as their topological intricacy, studied in the area of mathematics known as knot theory.
The fisherman's knot is a bend with a symmetrical structure consisting of two overhand knots, each tied around the standing part of the other. Other names for the fisherman's knot include: angler's knot, English knot, halibut knot, waterman's knot, and true lovers' knot.
The figure-eight knot or figure-of-eight knot is a type of stopper knot. It is very important in both sailing and rock climbing as a method of stopping ropes from running out of retaining devices. Like the overhand knot, which will jam under strain, often requiring the rope to be cut, the figure-eight will also jam, but is usually more easily undone than the overhand knot.
The figure-eight or figure-of-eight knot is also called the Flemish knot. The name figure-of-eight knot appears in Lever's Sheet Anchor; or, a Key to Rigging. The word "of" is nowadays usually omitted. The knot is the sailor's common single-strand stopper knot and is tied in the ends of tackle falls and running rigging, unless the latter is fitted with monkey's tails. It is used about ship wherever a temporary stopper knot is required. The figure-eight is much easier to untie than the overhand, it does not have the same tendency to jam and so injure the fiber, and is larger, stronger, and equally secure.
A whipping knot or whipping is a binding of marline twine or whipcord around the end of a rope to prevent its natural tendency to fray.
Figure-eight loop is a type of knot created by a loop on the bight. It is used in climbing and caving.
The Flemish loop or figure-eight loop is perhaps stronger than the loop knot. Neither of these knots is used at sea, as they are hard to untie. In hooking a tackle to any of the loops, if the loop is long enough it is better to arrange the rope as a cat's paw.
A climbing harness is a piece of equipment that allows a climber to tie in to the safety of a rope. It is used in rock and ice climbing, abseiling, and lowering; this is in contrast to other activities requiring ropes for access or safety such as industrial rope work, construction, and rescue and recovery, which use safety harnesses instead.
Webbing is a strong fabric woven as a flat strip or tube of varying width and fibres, often used in place of rope. It is a versatile component used in climbing, slacklining, furniture manufacturing, automobile safety, auto racing, towing, parachuting, military apparel, load securing, and many other fields.
A blood knot is a bend knot most usefully employed for joining sections of monofilament nylon line while maintaining a high portion of the line's inherent strength. Other knots used for this purpose can cause a substantial loss of strength. In fly fishing, this serves to build a leader of gradually decreasing diameter with the castable fly line attached at the large diameter end and the fly or hook at the small diameter end. The principal drawback to the blood knot is the dexterity required to tie it. It is also likely to jam, which is not a concern in fishing line, which is no great loss to cut, but may be a concern in normal rope. "Blood knot" may refer to "a double overhand knot tied in a cat-o'-nine-tails."
The barrel knot, called blood knot by Keith Rollo, is the best bend there is for small, stiff or slippery line. The ends may be trimmed short and the knot offers the least resistance possible when drawn through water.
The Munter hitch, also known as the Italian hitch, mezzo barcaiolo or the crossing hitch, is a simple adjustable knot, commonly used by climbers, cavers, and rescuers to control friction in a life-lining or belay system. To climbers, this hitch is also known as HMS, the abbreviation for the German term Halbmastwurfsicherung, meaning half clove hitch belay. This technique can be used with a special "pear-shaped" HMS locking carabiner, or any locking carabiner wide enough to take two turns of the rope.
Rope splicing in ropework is the forming of a semi-permanent joint between two ropes or two parts of the same rope by partly untwisting and then interweaving their strands. Splices can be used to form a stopper at the end of a line, to form a loop or an eye in a rope, or for joining two ropes together. Splices are preferred to knotted rope, since while a knot typically reduces the strength by 20–40%, a splice is capable of attaining a rope's full strength. However, splicing usually results in a thickening of the line and, if subsequently removed, leaves a distortion of the rope. Most types of splices are used on three-strand rope, but some can be done on 12-strand or greater single-braided rope, as well as most double braids.
The surgeon's knot is a surgical knot and is a simple modification to the reef knot. It adds an extra twist when tying the first throw, forming a double overhand knot. The additional turn provides more friction and can reduce loosening while the second half of the knot is tied. This knot is commonly used by surgeons in situations where it is important to maintain tension on a suture, giving it its name.
A beer knot is a bend used to join tubular webbing. Its most common application is in constructing slings used in rock climbing. Compared with the water knot, it has the advantages of a higher strength, smaller profile, and a cleaner appearance due to the lack of free-hanging tails. However, the beer knot can be more difficult to tie than the water knot, and one of the tails is hidden from view, making safety checks for adequate tail length more difficult.
The offset overhand bend is a knot used to join two ropes together end-to-end. It is formed by holding two rope ends next to each other and tying an overhand knot in them as if they were a single line. Due to its common use in several fields, this bend has become known by many names, such as thumb knot, openhand knot, one-sided overhand knot or flat overhand bend (FOB), though the terms "one-sided" and "flat" are considered incorrect.
The eye splice is a method of creating a permanent loop in the end of a rope by means of rope splicing.
Ashley's bend is a knot used to securely join the ends of two ropes together. It is similar to several related bend knots which consist of two interlocking overhand knots, and in particular the alpine butterfly bend. These related bends differ by the way the two constituent overhand knots are interlocked.
The double overhand knot or barrel knot is simply an extension of the regular overhand knot, made with one additional pass. The result is slightly larger and more difficult to untie. It forms the first part of the surgeon's knot and both sides of a double fisherman's knot. According to The Ashley Book of Knots, "A double overhand knot tied in a cat-o'-nine-tails is termed a blood knot."
A Yosemite bowline is a loop knot often perceived as having better security than a bowline. If the knot is not dressed correctly, it can potentially collapse into a noose, however testing reveals this alternative configuration to be strong and safe as a climbing tie-in.
The offset figure-eight bend is a poor knot that has been implicated in the deaths of several rock climbers. The knot may capsize (invert) under load, as shown in the figure, and this can happen repeatedly. Each inversion reduces the lengths of the tails. Once the tails are used up completely, the knot comes undone.
