Morse Code is an international code for relaying messages by wire or radio. These signals are called dots and dashes. The dots are the short signals, and the dashes are the long ones. The code was invented by Samuel Morse to use on his telegraph. The international signal used when someone was in trouble was SOS. These letters stood for three short signals, three long signals, and three short signals. It is still used today; however, by radiotelephone, the distress call is "Mayday."

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