Want the best from VICE News in your inbox? Sign up here.SEOUL — If you’ve never heard of “Baby Shark,” you’ve somehow missed one of the biggest cultural phenoms in recent memory.The “Baby Shark” video, consisting of a simple animation of a family of cute sharks, has over 2 billion views on YouTube. The catchy kids song nearly outranked Lady Gaga's "Shallows" on the Billboard charts, and there are hundreds of thousands of videos unofficially featuring it. For the true fan, there’s a live show featuring the Baby Shark family. And stores in Seoul are packed with hot-selling Baby Shark merch.“Baby Shark” isn’t an accidental hit. Pinkfong, the Korean educational entertainment brand that created “Baby Shark”, has become a toddler music juggernaut over the past few years — thanks in no small part to some serious expertise in what makes a song catch on. And thinking like a 3-year-old.“When we're working on our choreography, we have to create something for children so that they can easily copy us,” says Paik So-young, a content creator at Pinkfong. “We study which hand movement or leg movement will be fun for the children.”VICE News visited the Pinkfong headquarters in Seoul, South Korea, to see how baby hits are made.This segment originally aired March 15, 2019, on VICE News Tonight on HBO.