Last month, the YouTube video showing a cat saving a boy from a dog attack was shared around the world.
The so-called "Hero Cat" clip was the first to reach 20 million views in just five days. Back in 2012, it took almost a month for "Gangnam Style" to hit that mark. By the way, Psy's newest video has about 50 million views since it hit the web on Sunday. So what's changed? The LIST's Ariel Wesler explains.