Telegraph

Telegraphy is the long distance transmission of messages using symbolic codes known in advance to both sender and receiver, rather than by physically carrying an object that bears the message, so flag semaphore counts as telegraphy while a system such as pigeon post, which carries a physical object, does not. The earliest true telegraph in widespread use was the Chappe telegraph, an optical system invented by Claude Chappe in the late eighteenth century and used extensively across France and French occupied Europe during the Napoleonic era. The electric telegraph began replacing the optical telegraph in the mid nineteenth century, taken up in Britain as the Cooke and Wheatstone telegraph and, in the United States, through a separate system developed by Samuel Morse, whose code, in a version modified in Germany in 1848, was adopted as the international standard in 1865. Telegraph traffic later spurred automated systems such as teleprinters and punched tape transmission, but competition from the telephone drove the telegraph into decline from 1920 onward, and its few remaining uses were largely taken over by internet based alternatives by the end of the twentieth century.