braid

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"The braid" (1887) by Auguste Renoir.

..with more than 3 yarns

A braid (also called plait) is a complex structure or pattern formed by intertwining three or more strands of flexible material such as textile fibers, wire, or human hair. Compared to the process of weaving a wide sheet of cloth from two separate, perpendicular groups of strands (warp and weft), a braid is usually long and narrow, with each component strand functionally equivalent in zigzagging forward through the overlapping mass of the others.

The simplest possible braid is a flat, solid three-strand structure. More complex braids can be constructed from an arbitrary (but usually odd) number of strands to create a wider range of structures: wider ribbon-like bands, hollow or solid cylindrical cords, or broad mats which resemble a rudimentary perpendicular weave.

Braids are commonly used to make rope, decorative objects, and hairstyles (also see pigtails, French braid). Complex braids have been used to create hanging fiber artworks.

Braids were and still are a common form of expression in the African-American community. Some braids are very elaborate and show individuality of persons.^{[citation needed]}

Some men wear braids to keep their hair back but in a comfortable way. They may also be used for formal occasions.

Ropes and cables

A step by step creation of a basic braid using three strings.

Braiding creates a composite rope that is thicker and stronger than the non-interlaced strands of yarn. Braided ropes are preferred by arborists, rock climbers and in sport sailing because they do not twist under load, as does an ordinary twisted-strand rope. These ropes consist of one or more concentric tubular braided jackets surrounding a single untwisted yarn of straight fibers.

In electrical and electronic cables, braid is a tubular sheath made of braided strands of metal placed around a central cable for shielding against electromagnetic interference. The braid is grounded while the central conductor(s) carry the signal.

Another use is for litz wire which uses braids of thin insulated wires to carry high frequency signals with much lower losses from skin effect or to minimise proximity effect in transformers.

Flat braids made of many copper wires are also sometimes used for flexible electrical connections between large components. The numerous smaller wires comprising the braid are much more resistant to breaking under repeated motion and vibration than is a cable of larger wires.

Similar braiding is used on pressurized rubber hoses, such as in plumbing and hydraulic brake systems in automobiles. Braiding is also used for fibres for composite reinforcements.

A property of the basic braid is that removing one strand unlinks the other two, as they are not twisted around each other. Mathematically, a braid with that property is called a Brunnian braid.

Other braids

Gold braids and silver braids are components or trims of many kinds of formal dress, including military uniform (in epaulettes, aiguillettes, on headgear).

Metaphors

The braided streams of the Tanana River.

Braids are often used figuratively to represent interweaving or combination, such as in "He braided many different ideas into a new whole."

Braiding happens when a river is carrying vast amounts of eroded sediment. Sediment is deposited as islands in the channel causing the river to split up into many winding channels.

In some river and stream systems, small streams join together and redivide in many places. Such stream systems are said to be braided. These are often found in alluvial fans at the outlet of canyons. This is a result of heavy sediment deposition at high flows followed by re-erosion at low flows. See also river delta.

Gallery

A braid.

A coaxial cable with braided copper wire EMI shielding (B).

A gold braid on a police uniform.

See also

• Braid theory
• French braid
• Kumihimo, Japanese braid
• Stockwhip