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Answer: 1С 2G 3J, К, L 4P
Communication technology: a brief history
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| bet | 2/4 | | Sana | 19.11.2023 | | Hajmi | 89,94 Kb. | | #101551 |
Bog'liq 2 course reading and writing lesson 4Answer: 1С 2G 3J, К, L 4P
Communication technology: a brief history
Transcript of a speech given by Dr Elizabeth Wallace
A The 21st century is already being described as the 'Information Age', not surprisingly, since communication and information technologies are widespread - in our homes, workplaces, and
universities. It is probable that you have access to a mobile phone, radio, and television. It is equally likely that you have access to the global telecommunication network: the Internet. These forms of communication seem very modern, and yet the 'Information Age' of the early 21st century has a long and fascinating history.
The birth of electronic communication
В Deciding where to begin this history is difficult, but I would argue that our modern communication era started with the invention of telegraphy, literally, 'writing at a distance'. In 1830, scientist Joseph Henry used an electromagnet to force a steel bar to swing and ring a bell. This was the first electrical signalling.
C Samuel Morse developed this idea and invented the first practical telegraph in 1838. His system used an electrical circuit, a battery, a wire joining two telegraph stations, and an electromagnet.
When a key was pressed onto the wire, it completed the electrical circuit, and then when it was released, it broke the circuit. This produced a clicking sound. For ease of communication, he
developed the Morse code of dots and dashes.
D By the 1870s, news was travelling the world in seconds and many historic events such as the eruption of Krakatoa in 1883 and the sinking of the Titanic in 1912 were announced via the telegraph. However, despite this success, scientists and inventors were already considering how to transform the spoken word into electrical signals.
'Talking with electricity'
E Alexander Graham Bell understood the theory of a telephone, but struggled for a number of years to make a working model. Then, on March 10th 1876, he finally succeeded in transmitting speech.
Bell's first telephone did not resemble the telephones of today, and over the next 100 years it underwent many changes. A microphone was added to produce a stronger signal. Then, the telephone 'bell' was attached, and users were given a unique 'telephone number'. Once amplifiers were added in the late 1920s, a telephone system was established that allowed people to talk across continents – the era of long-distance phone calls had arrived.
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