The Wizard of Oz is a 1939 American musical fantasy film produced by Metro-Goldwyn-Mayer (MGM). An adaptation of L. Frank Baum's 1900 children's fantasy novel The Wonderful Wizard of Oz, it was primarily directed by Victor Fleming, who left production to take over the troubled Gone with the Wind. It stars Judy Garland, Frank Morgan, Ray Bolger, Bert Lahr, Jack Haley, Billie Burke and Margaret Hamilton. Noel Langley, Florence Ryerson and Edgar Allan Woolf received credit for the screenplay, while others made uncredited contributions. The music was composed by Harold Arlen and adapted by Herbert Stothart, with lyrics by Edgar "Yip" Harburg.

Musical film is a film genre in which songs by the characters are interwoven into the narrative, sometimes accompanied by dancing. The songs usually advance the plot or develop the film's characters, but in some cases, they serve merely as breaks in the storyline, often as elaborate "production numbers".