Grease is a musical with music, lyrics, and a book by Jim Jacobs and Warren Casey. Named after the 1950s United States working-class youth subculture known as greasers and set in 1959 at the fictional Rydell High School in Northwest Chicago (based on Taft High School in Chicago, Illinois, and named after rock singer Bobby Rydell), the musical follows ten working-class teenagers as they navigate the complexities of peer pressure, politics, personal core values, and love. The score borrows heavily from the sounds of early rock and roll.
https://en.wikipedia.org/wiki/Grease_(musical)