SOS

SOS is the international Morse Code distress signal. It consists of three dots, three dashes and three dots (..., ---, ...).

Although thought by some to mean Save Our Souls, in actuality the signal was agreed upon because it was easy enough for even an amateur to use or recognize, even with interference.

Its most famous first major use was with the sinking of The Titanic when the radio operators decided to use it in instead of the orignal distress signal, CQD (Come Quick, Distress).