Forty years ago, #PrinceCharles and #PrincessDiana officially opened Live Aid. They were royalty, to be sure, but pop royalty was waiting on stage at #Wembley Stadium in London, too, to make history. That’s because Live Aid performers didn't just play in London, but also at what was then John F. Kennedy Stadium in Philadelphia, Pennsylvania, resulting in a global phenomenon. #LiveAid was a "super concert," featuring 16 hours of rock music in two venues linked by satellite, so that people at home could watch too. More than a billion viewers in 110 countries were said to have watched the concert—organizers claimed that more than 40% of the population tuned in with many dialing in to make #donations. The benefit raised over $125 million for hunger relief aimed at Africa. At the link in our bio, read more about how Live Aid changed #charitable giving. (Photo: Hulton-Deutsch Collection/Corbis via Getty Images)