While searching the histroy of communication it is found that the early socities developed systems for sending simple messages or signals that could be seen or heard over a short distance, such as drumbeats, fire and smoke signals, or lantern beacons. And sometimes messages were attached to the legs of carrier pigeons that were released to fly home (this system was used until World War I, which started in 1914). The system like Semaphore systems (visual codes) of flags or flashing lights were employed to send messages over relatively short but difficult-to-cross distances, such as from hilltop to hilltop, or between ships at sea. In the early 1790s the French scientist and engineer Claude Chappe persuaded the French government to install a system of towers that used semaphore signals to send visual telegraphs along approved routes throughout the country. The system was copied in Great Britain and the United States.
Flag signalling systems such as the semaphore system were once used by the military to communicate from a distance at sea and on land. The flag positions shown here represent the 26 letters of the alphabet. Additional signals are used to indicate the end of a word, when an error has occurred, or when numbers are about to follow. Numbers are then sent using the same signals as those used for the first 10 letters of the alphabet.
Some ancient societies, such as the Roman or Byzantine empires, expanded their territorial control far beyond their original boundaries, and traded with distant neighbors. To hold on to their far-flung territories, they needed two technologies that have remained closely tied ever since: transportation and the ability to record information. Recorded messages had to be carried easily; therefore, lightweight forms of recording (such as papyrus or animal skins) were desirable.
Flag signalling systems such as the semaphore system were once used by the military to communicate from a distance at sea and on land. The flag positions shown here represent the 26 letters of the alphabet. Additional signals are used to indicate the end of a word, when an error has occurred, or when numbers are about to follow. Numbers are then sent using the same signals as those used for the first 10 letters of the alphabet.
Some ancient societies, such as the Roman or Byzantine empires, expanded their territorial control far beyond their original boundaries, and traded with distant neighbors. To hold on to their far-flung territories, they needed two technologies that have remained closely tied ever since: transportation and the ability to record information. Recorded messages had to be carried easily; therefore, lightweight forms of recording (such as papyrus or animal skins) were desirable.
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