In 1973, in the rec room of a Bronx apartment building, Clive Campbell—stage name: DJ Kool Herc—and his sister, Cindy, put on a “Back to School Jam” party. Hip-hop was invented then and there, at 1520 Sedgwick Avenue. That year, every crumbling street corner in the Bronx sprang alive with newly minted Masters of Ceremony (or “M.C.s,” as they became known) and nascent D.J.s, who remixed dated disco records. In 1979, “Rapper’s Delight,” by the Sugarhill Gang, hit the Billboard Hot 100 chart. Over the next 10 years the obscure musical genre climbed into the mainstream. In this exhibition, which celebrates the movement’s 50-year anniversary, 100 works by the likes of Julie Mehretu, Tsch­a­balala Self, Arthur Jafa, Virgil Abloh, and Gordon Parks are on view. —Elena Clavarino