1. Grease is the Word!

    #OnThisDay in 1978, the "Grease" soundtrack hit no. 1 in the U.S. Tracks like "Grease," performed by Frankie Valli, and "You're The One That I Want," an upbeat duet between John Travolta and Olivia Newton-John, both peaked at no. 1 on the pop chart earlier in the year and boosted