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Definition of SOS

SOS is the most widely used international distress signal, and its origins date back to the early 20th century. In popular culture it has been assigned several meanings, such as ‘Save Our Ship’, ‘Save Our Souls’ or ‘Send Out Soccour’.

There is also an emoji, as a symbol of distress and it is also related to asking for help.


  1. Help


It has its origins in the early twentieth century, until then the distress signal used in telegraph transmissions in Morse code was ‘CQD’ ‘Copy Quality’ or Quality test, which was the call code for radio stations operating in the same band, along with ‘Distress’ which meant trouble.

The SOS sequence was imposed as the standard distress signal during the International Radiotelegraph Convention in Berlin on November 3, 1906.
It has been assigned various meanings according to the initials of English words, but according to some scholars, these theories are not justified by the simple fact that English is a sort of universal language.
They have looked further and have a Latin meaning for the sequence: ‘Si Opus Sit’. It can be translated as ‘when necessary’.

Thus, it would become the abbreviation of a phrase with a context of urgency that has come to mean ‘it is necessary’ and, from there, ‘help is needed immediately’.
However, the reality is that these three letters are not officially part of any acronym, nor do they have any meaning. This representation was only chosen for its ease of being radiated using Morse code, as it is a succession of three short pulses, three long pulses and three short pulses.

Given its simplicity, it was less likely to be misinterpreted or lost due to interference.
So it is not a matter of three separate letters, but of a continuous and unique code. Thus, and correcting what is usually believed, this SOS sequence was chosen because it is so simple to transmit and so easy to memorize.


We all know this code, because at some point we have seen in a movie or heard or read about the letters SOS, whether they are written on a beach because of a shipwreck or emitted in Morse code by a ship after an accident at sea.

It is often mistakenly thought that the first time the famous sequence was used was when the ‘Titanic’, the famous ship, sank, but other ships had already used this signal before.