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 butterfly loop, also known as lineman's loop, butterfly knot, alpine butterfly knot, Swiss loop and lineman's rider, is a knot used to form a fixed loop in the middle of a rope. Tied in the bight, it can be made in a rope without access to either of the ends; this is a distinct advantage when working with long climbing ropes. The butterfly loop is an excellent mid-line rigging knot; it handles multi-directional loading well and has a symmetrical shape that makes it easy to inspect. In a climbing context it is also useful for traverse lines, some anchors, shortening rope slings, and for isolating damaged sections of rope.
The constrictor knot is one of the most effective binding knots. Simple and secure, it is a harsh knot that can be difficult or impossible to untie once tightened. It is made similarly to a clove hitch but with one end passed under the other, forming an overhand knot under a riding turn. The double constrictor knot is an even more robust variation that features two riding turns.
The Eskimo bowline, Cossack knot, reverse bowline, or 'anti-bowline' is in a class of knots known as 'eye knots' or 'loop knots'. The eye is formed in the end of the rope to permit attachments/connections. It is quite common in Russia and is often used instead of the bowline. In the simple bowline, the collar component forms around the 'standing part'. In contrast, the collar component of an Eskimo bowline forms around the outgoing eye-leg.
The butterfly bend is a knot used to join the ends of two ropes together. It is the analogous bend form of the butterfly loop, in that it is the butterfly loop with the loop cut. The observation that the butterfly loop is secure enough to isolate a worn or damaged section of rope within the loop indicated that the bend form of the knot would be similarly secure.
The carrick mat is a flat woven decorative knot which can be used as a mat or pad. Its name is based on the mat's decorative-type carrick bend with the ends connected together, forming an endless knot. A larger form, called the prolong knot, is made by expanding the basic carrick mat by extending, twisting, and overlapping its outer bights, then weaving the free ends through them. This process may be repeated to produce an arbitrarily long mat.
A zeppelin bend is an end-to-end joining knot formed by two symmetrically interlinked overhand knots. It is stable, secure, and highly resistant to jamming. It is also resistant to the effects of slack shaking and cyclic loading.
A grief knot is a knot which combines the features of a granny knot and a thief knot, producing a result which is not generally useful for working purposes. The word grief does not carry its usual meaning but is a portmanteau of granny and thief.
The heaving line bend is a knot for securely joining two ropes of different diameter or rigidity. It is often used to affix playing strings to the thick silk eyes of an anchorage knot in some stringed instruments. In nautical use, the heaving line bend is used to connect a lighter messenger line to a hawser when mooring ships. It is knot number 1463 in The Ashley Book of Knots, and appeared in the 1916 Swedish knot manual Om Knutar.
The Carrick bend, also known as the Sailor's breastplate, is a knot used for joining two lines. It is particularly appropriate for very heavy rope or cable that is too large and stiff to be easily formed into other common bends. It will not jam even after carrying a significant load or being soaked with water.
The sheet bend is a bend. It is practical for joining lines of different diameter or rigidity.
An icicle hitch is a knot that is excellent for connecting to a post when weight is applied to an end running parallel to the post in a specific direction. This type of hitch will hold its place even when holding a substantial load on a smooth surface. One can even suspend from a tapered post with this knot.
The buntline hitch is a knot used for attaching a rope to an object. It is formed by passing the working end around an object, then making a clove hitch around the rope's standing part and taking care that the turns of the clove hitch progress towards the object rather than away from it. Secure and easily tied, the buntline hitch will jam when subjected to extreme loads. Given the knot's propensity to jam, it is often made in slipped form.
The buntline hitch, when bent to a yard, makes a more secure knot than two half hitches, but is more liable to jam. It differs from two half hitches in that the second half hitch is inside instead of outside the first one.
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.
The Ashley Book of Knots is an encyclopedia of knots written and illustrated by the American sailor and artist Clifford W. Ashley. First published in 1944, it was the culmination of over 11 years of work. The book contains 3,857 numbered entries and approximately 7,000 illustrations. The entries include knot instructions, uses, and some histories, categorized by type or function. It remains one of the most important and comprehensive books on knots.
The bottle sling is a knot which can be used to create a handle for a glass or ceramic container with a slippery narrow neck, as long as the neck widens slightly near the top.
The International Guild of Knot Tyers is a worldwide association for people with an interest in knots and knot tying.
The fiador knot is a decorative, symmetrical knot used in equine applications to create items such as rope halters, hobbles, and components of the fiador on some hackamore designs. As traditionally described, it is a four strand diamond knot in which six of the eight ends loop back into the knot, thus allowing it to be tied with a single line. While a specific knot is discussed in this article, the fiador knot has also been treated as an entire class of multi-strand knots similarly made with a single line.
In knot tying, a bight is a curved section or slack part between the two ends of a rope, string, or yarn. A knot that can be tied using only the bight of a rope, without access to the ends, is described as in the bight. The term "bight" is also used in a more specific way when describing Turk's head knots, indicating how many repetitions of braiding are made in the circuit of a given knot.
The Lapp knot is an ends joint, i.e. it is used to join two cordage ends. It is essentially a reverse sheet bend. The slipped Lapp bend also is an exploding knot, which means that when pulling the quick release end it falls completely apart without further entanglement. It is as strong as or even stronger than the sheet bend, though much less common.
