Samuel Morse invented Morse code in 1836. Samuel Morse was a famous American painter and inventor who began to seriously pursue his interest in electricity in 1827. Morse also helped to invent the telegraph, which was used to transmit messages in Morse code.
Information sent over telegraphs was sent in the form of electric signals. Short signals were called "dits," and were represented by dots, and long signals were "dahs," represented by dashes. This system of Morse code relied on the exact time intervals between the dits and dahs, which were decoded into letters and words, most famously the phrase SOS. An experienced Morse code operator could transmit and receive 20 to 30 words per minute.