After the sinking of the "Titanic," the United States officially adopted the SOS as its distress signal. The use of SOS soon became universal, and the standard signal ruled the high seas until ...

And not just one fire, but ideally three. Three of anything is considered the universal signal of distress: three fires, three blows in a whistle, three gunshots. Think of the original SOS call ...

The hand signal, now viral on Instagram, involves tucking your fingers over your thumb to reportedly alert someone you need help.

Best known for its appearances in desert-island cartoons, maritime movies and earworms by ABBA and Rihanna, the word SOS has been used as a code for emergency distress signals since 1905.

The electrochemical sensor attaches directly to live plant leaves and monitors hydrogen peroxide, a key distress signal. Environmental conditions can cause damaging stress to plants, posing ...