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International Morse Code

communications
Also known as: Continental Morse Code

Quick Summary

International Morse Code is a system for representing letters, numbers, and punctuation using dots, dashes, and spaces. These codes are transmitted as electrical pulses or visual signals, like flashing lights.123

The original "American" Morse Code was developed by Samuel F.B. Morse in the 1830s for telegraphy, with improvements by Alfred Vail. However, the International Morse Code, devised by European nations in 1851, became the global standard due to its simplicity and precision, using combinations of dots and short dashes for all letters. The universal distress signal "SOS" is a well-known example: three dots (S), three dashes (O), and three dots (S).12

While the original American Morse Code is rarely used today, International Morse Code is still employed by U.S. Navy intelligence specialists, amateur radio operators, and aviators. It played a significant role in World War II and subsequent conflicts, and was crucial for maritime safety until the early 1990s.12

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