Means of Communication

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Millennium after millennium people communicate only by using the propagation of sound in a continuous medium - air. To send messages over long distances used primitive methods, like smoke signals or drums. An invention is a device that for the transmission and reception of sound would use the properties of electricity, was preceded by the appearance of the electric telegraph and its successful application in the first half of the XIX century.

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February 14, 1876 Irish-American, Alexander Graham Bell filed a US Patent Office application for the invention of the machine, which he called the telephone. Just two hours later, a similar request made by another American names Gray. Improvement of telephone devices took over many other inventors, and 1900 in this area it has been issued more than 3 thousand patents.

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Old and new phone numbers

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Today, the role of mobile phone in one's life is hard to overestimate. With this compact device at any time, we can quickly contact their relatives and friends. Mobile phone in a person's life is an indispensable tool, it brings benefits to those who value their time and are not willing to spend it in vain. The use of mobile phone is obvious - saving time and money.

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For business people use a cell phone is the ability to negotiate, to reach an agreement with our partners at any time and in any place. Mobile phone in the life of some people, it is also part of the image. And whoever gets in difficult conditions and circumstances, knows what benefit, carries a cell phone. Often, it is mobile phones are saving people's lives, saves them from danger and help in difficult situations.

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The damage from a cell phone Scientists have found that mobile telephony - a source of harmful electromagnetic radiation on human health. Now it is proved that electromagnetic waves stimulate changes at the cellular level, causing violations of gene order, contribute to the appearance of diseased cells and disease-causing tumors .

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In recent years, cell phones have become an integral part of our lives. This is not surprising, since a high rhythm of life, the realization of the goals and objectives of everyday dictates the need to be always in touch and have on hand a faithful assistant. That is our right phone replaces the notebook and flash-drive. And all sorts of useful software features, options which are equipped with modern cell phones do a small-sized device is so multifunctional that sometimes you wonder. Impressive, and what the pace is tremendous development of cell phones, every day there are more and more new model s.