International Morse Code

International Morse Code, system of signals employed in radiotelegraphy in the land-telegraph systems of all countries except the United States and Canada, and by all countries in flash lamp communications in marine navigation (see Telegraph). The system is an adaptation of Morse code, the original telegraphic alphabet that American inventor Samuel F. B. Morse devised with help from other contemporary scientists. The United States and Canada did not adopt the International Morse Code for sending telegraphy messages when other countries did in the 1850s; instead, the United States and Canada continued to use the original Morse code. International Morse Code consists of combinations of dots and dashes representing the letters of the alphabet and numerals, as shown in the accompanying table. The duration of one dash equals that of three dots. Today, International Morse Code is no longer used commercially or by the military, because radiotelegraphy has been replaced by digital communications via satellite. See also International Code of Signals.