SOS

distress signal

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July 14, 2026

Quick Summary

SOS is an internationally recognized distress signal, primarily used by ships and aircraft to call for assistance when in danger. It is transmitted using International Morse Code as a sequence of three dots, three dashes, and three dots (...---...). This pattern represents the letters S, O, and S, but SOS is not an acronym for phrases like "save our ship" or "save our souls". The sequence was adopted because it is simple, easy to remember, and effective for communication in emergencies. SOS is also used on wireless devices to indicate a loss of cellular network access, allowing only emergency calls.123

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Today in History—April 15
The Titanic’s Final Moments and Messages
…later also sent the newer SOS signal.
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…later also sent the newer SOS signal.
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distress signal
…such as the Morse group SOS, the international code signal NC, or the spoken word “Mayday” (pronounced like the French m’aider, “help me”), by radiotelephone. Distressed vessels may also actuate alarms of other vessels by a radio signal consisting of a series of 12 four-second dashes or by a radiotelephone…
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…such as the Morse group SOS, the international code signal NC, or the spoken word “Mayday” (pronounced like the French m’aider, “help me”), by radiotelephone. Distressed vessels may also actuate alarms of other vessels by a radio signal consisting of a series of 12 four-second dashes or by a radiotelephone…
Read More

What Does SOS Mean?
SOS is communicated by sending three dots, three dashes, and three dots—three dots representing the letter “S” and three dashes representing the letter “O.” This sequence is simple and easy to remember, making it an effective way to notify others of an emergency. SOS is…
Read More
SOS is communicated by sending three dots, three dashes, and three dots—three dots representing the letter “S” and three dashes representing the letter “O.” This sequence is simple and easy to remember, making it an effective way to notify others of an emergency. SOS is…
Read More