"Do-Re-Mi (Money)" is a song from the musical The Sound of Music, written by Richard Rodgers and Oscar Hammerstein II. The song uses the musical scale to explain the concept of money, associating each note with a different aspect of financial life. It highlights how money can be both a necessity and a source of happiness. In the song, the characters illustrate how money can be used for various purposes, such as buying things or providing security. The playful lyrics emphasize the importance of understanding money while also enjoying life, making it relatable to audiences of all ages.