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The history of telecommunication predates what is commonly thought of as modern ideas and the systems currently in place today. While the Internet is a major form of telecommunication in todays world its concept is far from new.

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[edit] Telegraphy

The first telegraph links in Europe.
The first telegraph links in Europe.
مک مقالو: Telegraphy

[edit] Optical

The first telegraphs were optical telegraphs, including the use of smoke signals and beacons. These have existed since ancient times. A semaphore network invented by Claude Chappe operated in France from 1792 and remained in operation until 1846. It helped Napoleon enough that it was widely imitated in Europe and the United States. The last (Swedish) commercial semaphore link left operation in 1880.

[edit] Electromagnetic and electrical

The first electromagnetic telegraph was created by Baron Schilling in 1832. The first commercial electrical telegraph was constructed by Sir Charles Wheatstone and Sir William Fothergill Cooke and entered use on the Great Western Railway. It ran for 13 miles from Paddington station to West Drayton and came into operation on 9 April 1839. It was patented in the United Kingdom in 1837.

An electrical telegraph was independently developed and patented in the United States in 1837 by Samuel Morse. He developed the Morse code signalling alphabet with his assistant, Alfred Vail. The Morse/Vail telegraph was quickly deployed in the following two decades.

The first transatlantic telegraph cable was successfully completed on 27 July 1866, allowing transatlantic telegraph communications for the first time. Earlier submarine cable transatlantic cables installed in 1857 and 1858 only operated for a few days or weeks before they failed. The study of underwater telegraph cables accelerated interest in mathematical analysis of these transmission lines.

On 9 August 1892 Thomas Edison received a patent for a two-way telegraph.

[edit] Early wireless communication

[edit] Wireless telegraphy

As far back as Faraday and Hertz in the early 1800s, it was clear to most scientists that wireless communication was possible, and many people worked on developing many devices and improvements. In 1832, James Bowman Lindsay gave a classroom demonstration of wireless telegraphy to his students. By 1854 he was able to demonstrate transmission across the Firth of Tay from Dundee to Woodhaven (now part of Newport-on-Tay), a distance of two miles.

Patents for wireless telegraphy devices started appearing in the 1860s but it was not until 1893 that Nikola Tesla made the first public demonstration of such a system. Addressing the Franklin Institute in Philadelphia and the National Electric Light Association, he described and demonstrated in detail the principles of wireless telegraphy. The apparatus that he used contained all the elements that were incorporated into radio systems before the development of the vacuum tube.

The later derived system (which used several patents of Tesla's) that achieved widespread use was demonstrated by Guglielmo Marconi in 1896. Marconi and Braun shared the 1909 Nobel Prize in physics for "contributions to the development of wireless telegraphy".

[edit] Radio communication

مک مقالو: History of radio

A few decades later, the term radio became more popular. Early radio could not transfer sounds, only Morse code in the tones made by rotary spark gaps. Canadian-American scientist Reginald Aubrey Fessenden was the first to wirelessly transmit a human voice (his own) in 1900.

After the public demonstrations of radio communication that Tesla made in 1893, the principle of radio communication – sending signals through space to receivers – was publicised widely. The Telsa apparatus contained all the elements of radio systems used before the development of the vacuum tube.

On 19 August 1894, British physicist Sir Oliver Lodge demonstrated the reception of Morse code signalling using radio waves using a detecting device called a coherer, a tube filled with iron filings which had been invented by Temistocle Calzecchi-Onesti at Fermo in Italy in 1884.

The first benefit to come from radio telegraphy was the ability to establish communication between coast radio stations and ships at sea. Wireless telegraphy using spark gap transmitters quickly became universal on large ships after the sinking of the RMS Titanic in 1912. The International Convention for the Safety of Life at Sea was convened in 1913 and produced a treaty requiring shipboard radio stations be manned 24 hours a day.

[edit] Telephone

مک مقالو: Telephone

[edit] Television

مک مقالو: Television

[edit] The Internet

مک مقالو: History of the Internet

[edit] External links