Grandmaster Flash, born Joseph Robert Saddler on January 1, 1958, is a pioneering Barbadian-American DJ and innovator in hip hop music. He is best known for developing the Quick Mix Theory, a revolutionary DJ technique that used duplicate vinyl records to extend drum breaks, paving the way for cutting and scratching in DJ culture and greatly enhancing the music for rappers and breakdancers. He also invented the slipmat, an essential DJ tool. As the founder of Grandmaster Flash and the Furious Five, he led the first rap group inducted into the Rock and Roll Hall of Fame in 2007. Grandmaster Flash has received numerous accolades, including the Polar Music Prize in 2019 and honorary doctorates from Buffalo State University and Lehman College. In 2023, New York City dedicated August 4 as Grandmaster Flash Day in his honor.