Jr. Gong, Stephen Marley, Cham, Sean Paul — the list goes on. A massive jam session ensues and nearly everyone leaps onstage to spit some lyrics. To call this reggae history is no hyperbole. Empress K/For NPR hide caption

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"If I trust you with the power of human life, your standard has to be much higher," says rapper Killer Mike, son of a policeman, on police violence. Courtesy of the artist hide caption

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"There was a lot of tears. There was a lot of anguish," Jimmy Greene says of writing Beautiful Life. Jimmy & Dena Katz/Courtesy of the artist hide caption

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Herbie Hancock and Pharrell Williams performed Williams' hit "Happy" at the 2014 Thelonious Monk International Jazz Trumpet Competition. Imeh Akpanudosen/Getty Images for Thelonious Monk Institute of Jazz hide caption

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Sleater-Kinney's Janet Weiss (left), Carrie Brownstein (center) and Corin Tucker (right) join All Songs Considered hosts Bob Boilen and Robin Hilton to discuss new album No Cities To Love. Courtesy of the artist hide caption

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