"Do-Re-Mi" is a show tune from the 1959 Rodgers and Hammerstein musical The Sound of Music. Within the story, it is used by Maria to teach the notes of the major musical scale to the Von Trapp children who learn to sing for the first time, even though their father has disallowed frivolity after their mother's death. The song is notable in that each syllable of the musical solfege system appears in its lyrics, sung on the pitch it names.
In the stage version, Maria sings this song in the living room of Captain von Trapp's house, shortly after she introduces herself to the children. However, when Ernest Lehman adapted the stage script into a screenplay for the 1965 film adaptation, he moved the song to later on in the story. In the film, Maria and the children sing this song over a montage as they wander and frolic over Salzburg.
The song soon became popular in its own right. It is often sung in day care centers. It is also often one of the first songs that children will learn to play on simple children's instruments that have only the eight notes of one octave of the major C to C scale. It was originally written in this key in the sheet music and is sung this way in the original stage version of The Sound of Music. However, in the film version it was transposed from C to B flat.