While most of us know this song from The Sound of Music (1965), it first appeared in the 1959 musical of the same name and it was composed by Richard Rodgers. As a bit of trivia information, Rodgers was the first one to win an Emmy, a Grammy, an Oscar, and a Tony for his work, a collection of awards that is called EGOT (11 people have won it until now, besides him).
The song is a pretty easy one to follow, because of its simple lyrics which are meant to teach little children the musical notes of the solfeggio. While in the stage version the song is heard in the beginning of the play, in the film it is heard later on, during a montage in which Maria and the children are seen all around Salzburg.
Everybody knows that this is a homophonic (or near-homophonic) method of learning the musical notes, each note being linked with objects, animals, pronouns, and so on. However, there is a problem with one of the notes, with La, for which Richard Rodgers didn’t find an appropriate homophone.
There is even a story which says that Rodgers wasn’t satisfied by this line so he just wrote it down with the intention of finding something suitable later on. As it appears, this never happened.
The song is, nonetheless, an influential one, being included at number 88 in AFI’s 100 Years…100 Songs. As you might have guessed, it was featured heavily in the pop-culture.
Anita Bryant was the first one to make a cover, even before the movie arrived, in 1959. Her song entered the Billboard Hot 100, although it didn’t reach a better position than 94.
In 1992, Madonna references Do-Re-Mi in in her hit Deeper and Deeper, by using the line When you know the notes to sing, you can sing most anything (which is actually taken from the original song).
Simpsons also makes a reference in the episode Bart Gets an Elephant. After Homer crashes into a statue, he says his iconic line (if it can be called so) D’oh, to which Lisa says A deer, while Marge completes with A female deer.
Lastly, and probably the best reference is actually a parody of the song and it can be seen in Ghostbusters 2, when the main characters power-up their proton packs. Peter Venkman says Do, Raymond Stantz says Re, while Egon Spengler says Egooon.