Did you know that Calum Hood was never actually asked to be in Australian pop-rock outfit 5 Seconds of Summer? Or that drummer Ashton Irwin is completely self-taught on a set of drums his grandparents bought him thinking they'd go largely unused? Well, strap on your seat belts, 5SOS Fam, because we're diving in deep for some serious 5 Seconds of Summer trivia in the latest episode of our, ahem, educational video series, Think You Know Pop?

Yes, we've all come to love the punky (and underage) four-piece from Sydney, and we watched with our jaws on the floor as the boys took home the Best Fan Army trophy at the 2015 iHeartRadio Music Awards and during their slime-tastic performance of "What I Like About You" at the 2015 Kids' Choice Awards. Now the spotlight is back on them, and in the video above, you'll find out exactly how to play "derpball"; the official opinion held by Luke, Michael, Claum and Ashton on some very trendy underpants; and why we've nominated a banana as the band's mascot.

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