Device that constrains the path of electromagnetic waves (see electromagnetic radiation). It can be used to transmit power or signals in the form of waves while minimizing power loss. Common examples are metallic tubes, coaxial cables, and optical fibres (see fibre optics). Waveguides transmit energy by propagating transmitted electromagnetic waves through the inside of a tube to a receiver at the other end. Metal waveguides are used in such technologies as microwave ovens, radar systems, radio relay systems, and radio telescopes.

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or Seeing Eye dog

Dog professionally trained to guide and protect its blind master. They have also been used to assist persons with hearing impairments and restricted mobility. Systematic training of guide dogs originated in Germany during World War I to aid blinded veterans. At the age of approximately one year, the dog is trained for three or four months. Retrievers and German shepherds are the most widely used breeds.

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A guide is a person who leads people through unknown or unmapped country, or conducts travellers and tourists through a place of interest.

Etymology

The word "guide" was incorporated into (Middle) English via Old French "guider" which meant "to guide, lead, conduct" it was originally taken by Old French from Frankish "*witan" meaning "show the way" (compare modern Dutch "weten") from Proto-Germanic "*wit-" meaning "to know" (compare Old English "witan" meaning "to see"). The French word influenced by Old Provencal "guidar" meaning "guide or leader" is from the same source.

Tourist guide

A person who guides visitors in the language of their choice and interprets the cultural and natural heritage of an area. The guide will normally possess an area-specific qualification usually issued and/or recognised by the appropriate authority. Tourist Guides are representatives of the cities, regions and countries for which they are qualified. It depends largely on them if visitors feel welcome, want to stay longer or decide to come back. They therefore contribute considerably to the perception of the destination. Tourist Guides are able to help travellers understand the culture of the region visited and the way of life of its inhabitants. They have a particular role on the one hand to promote the cultural and natural heritage whilst on the other hand to help ensure its sustainability by making visitors aware of its importance and vulnerability. [EN 13809:2003]

Mountain guide

Mountain guides are those employed in mountaineering; these are not merely to show the way but stand in the position of professional climbers with an expert knowledge of rock and snowcraft, which they impart to the amateur, at the same time assuring the safety of the climbing party. This professional class of guides arose in the middle of the 19th century when Alpine climbing became recognized as a sport.

In Switzerland, the central committee of the Swiss Alpine Club issues a guides’ tariff which fixes the charges for guides and porters; there are three sections, for the Valais and Vaudois Alps, for the Bernese Oberland, and for central and eastern Switzerland.

In Chamonix (France)a statue has been raised to Jacques Balmat, who was the first to climb Mont Blanc in 1786. Other notable European guides are Auguste Balmat, Michel Cros, Maquignay, J. A. Carrel, who accompanied Edward Whymper to the Andes, the brothers Lauener, Christian Almer and Jakob and Melchior Anderegg.

Hunting guide

Guides have been employed by those seeking to hunt, or sometimes only to photograph or see, wildlife, especially big game animals in the wild. Hunting guides have been important in many areas of the world, including Africa, the American west, the Adirondacks, etc.

Metaphysical guide

Trip sitter

A psychedelic guide is someone who guides a drug user's experiences as opposed to a sitter who merely remains present, ready to discourage bad trips and handle emergencies but not otherwise getting involved. Guides are more common amongst spiritual users of entheogens. Psychedelic guides were strongly encouraged by Timothy Leary and the other authors of The Psychedelic Experience: A Guide Based on the Tibetan Book of the Dead. Trip sitters are also mentioned in the Responsible Drug User's Oath.

Guided meditation

Military guide and development of Guides Regiments

In European wars up to the time of the French Revolution, the absence of large-scale detailed maps made local guides almost essential to the direction of military operations. In the 18th century the stricter organization of military resources led in various countries to the special training of guide officers who had the primary duty of finding, and if necessary establishing, routes across country.

The genesis of the "Guides" regiments may be found in a short-lived Corps of Guides formed by Napoleon in Italy in 1796, which appears to have been a personal escort or body guard composed of men who knew the country. Following the unification of Italy in 1870-71, the new national army included a regiment designated as Guides - the 19th Cavalleggieri (Light Horse).

In the Belgian army the two Guides regiments constituted part of the light cavalry, and came to correspond to the Guard cavalry of other nations.

In the Swiss army prior to 1914 the squadrons of "Guides" acted as divisional cavalry. In this role these light cavalry units were called upon, on occasion, to lead columns.

The "Queen’s own Corps of Guides" of the British Indian Army consisted of a unique combination of infantry companies and cavalry squadrons. After World War I the infantry element was incorporated in the 12th Frontier Force Regiment and the Guides Cavalry formed a separate regiment.

In drill, a "guide" is an officer or non-commissioned officer who regulates the direction and pace of movements.

In the history of the American west, Native Americans and mountain men were important in leading military units and settlers alike.

Other Usages

In the Indian academia, the word guide is referred to the person who helps prepare a Doctorate or Ph.D. thesis.

References

Original text from the 1911 Encyclopædia Britannica.