How SOS Became the Universal Distress Signal

The telegraph and Morse code were developed in the 1840s, but the system was no use for ships at sea because it required wires. But then Marconi gave us a wireless telegraph system, or "radio," first demonstrated in 1896. Suddenly, communications from ships at sea was possible, but it took some time and some left turns to work out standard international codes. The most important was a distress signal, calling any available ships for immediate aid. For some time, this code was CQD. Simon Whistler of Today I Found Out explains how that got turned into the SOS signal that we all recognize today. (via Laughing Squid) 

I got a kick out of how Whistler pronounces Cape Hatteras as Hatter Ass.