The telegraph
This is the Electrical telegraph owned and built by Samuel Morse.
Source: Wikipedia 
. Image released under GFDL with author’s permission.
(tele = distance, graph = writing)
Telegraphs were systems used to send messages over long distances. While the term today is normally used to refer to the electrical telegraph, there were other types of telegraphic devices used to send messages before this invention.
These included optical telegraphs, using smoke signals and beacons and the mechanical telegraph, which used mechanically-operated arms that could move into different positions to communicate a code.
The mechanical telegraph, using a semaphore system, was particularly popular in France after its introduction by Napoleon in 1792. However, it was rapidly overtaken by the electrical telegraph using a wire to send electrical signals. The last mechanical telegraph in Europe was closed down by 1880.
The electrical telegraph was developed during the 1830s and involved the translating of written messages into a code then sending them electrically over a wire.
However, it was with a message sent on 24 May 1844 by Samuel Morse that made the telegraph became famous. Samuel Morse was the creator of the Morse code and went on to become the founder of the first practical telegraph system. His message “What hath God wrought” was sent from the Supreme Court chamber in Washington D.C to a railroad depot in Baltimore, Maryland.
Morse code
The electrical telegraph could only send electrical signals so it became important to develop a shorthand way to represent letters and words to reduce time required to send messages. The most widely used telegraph code system was Morse code invented by Samuel Morse. The code used long and short electrical impulses, sometimes represented as dots and dashes, to convey letters of the alphabet along a wire. Each message was transcribed from dots and dashes into words and sentences.
Growth of telegraphy
A map of major telegraph lines in 1891.
Source: Wikipedia .
The first public telegraph companies began operating in the 1840s and by 1850 wires were laid underwater across the English Channel to link Britain and Europe.
The first successful trans-Atlantic telegraph began operating in 1866 after several earlier attempts to lay a cable under the sea failed. This was the first time the 'old world', Europe, and the 'new world', America, had a system of communication faster than a mail ship.
Samuel McGowan introduced Morse code to Australia in 1853, and telegraph cables were set up across the country by 1859. Australia took to the telegraph enthusiastically, at one point becoming the world’s most frequent senders of telegrams. An ambitious attempt to cross the continent from south to north with a telegraph wire, from Port Augusta to Darwin, succeeded by 1872. This was connected with an English cable from Java, becoming Australia’s first telecommunications link with the rest of the world.
Over the next few decades underwater cables were used to link many other parts of the world to the telegraph, creating a global network which has since been called ‘the Victorian internet’.
However, as technology advanced, wireless telegraphy enabled people to send messages over long distance using radio. The telephone was also invented and rapidly began replacing telegraph connections.
However, the tradition of sending telegrams on important occasions such as for births persisted for a long time into the twentieth century.
It was only recently, on 27 January 2006, when Western Union closed its telegram service, that this telecommunications era was considered to have ended.