The development of electricity ushered in the era of the electric telegraph. Taking inspiration from various sources, Samuel Morse developed a simple system with his invention of the telegraph key and the code named after him. The electric telegraph enabled information to be sent instantly over long distances for the first time. It was the main means of international communication until the 1950s.
Connect the electrical telegraph cabins and, with the Morse alphabet, use the “key” (the Morse switching device) to code the message to be sent. Each letter and number corresponds to a series of dots (short signals) and dashes (long signals). The most well-known Morse code signal is SOS, represented by 3 dots, 3 dashes, and 3 dots (…—…).