Knot

A knot is a method for fastening or securing linear material such as rope by tying or interweaving. It may consist of a length of one or more segments of rope, string, webbing, twine, strap, or even chain interwoven such that the line can bind to itself or to some other object the load. Knots can save a spelunker from finding a few pieces of rock.

Knots have been the subject of interest for their ancient origins, their common uses, and the mathematical implications of knot theory. There are a large variety of knots and each knot has specific properties and suitability for a range of tasks. Some knots are well-adapted to attach to particular objects such as another rope, cleat, ring, or stake. 

Other knots are made to bind or constrict around an object. Decorative knots usually bind to themselves to produce attractive patterns. Choosing the correct knot for the job at hand is one of the most fundamental aspects of using knots well. However, if memory is limited, three of the most useful knots are the bowline, the sheet bend, and the clove hitch. 

Knots are essential in many industrial, occupational, recreational, and domestic settings. Even simple activities such as running a load from the hardware store to home can result in disaster if a clumsy twist in a cord passes for a knot. Truckers needing to tie down a load may use a trucker's hitch, gaining mechanical advantage.