Origins of the Morse Code (1837)

in 1837 Samuel F. B. Morse invented a practical form of electromagnetic telegraph using an early version of his “Morse code.” 

Morse originally devised a cipher code similar to that used in existing semaphore telegraphs, by which words were assigned three or four-digit numbers and entered into a codebook. The sending operator converted words to these number groups and the receiving operator converted them back to words using this codebook. Morse spent several months compiling this code dictionary.