Songs like Dixie , The Battle Hymn of the Republic and Marching Through Georgia contained choruses that stirred people to action and became part of the movements they represented. After the Civil War ended, this song form found its way into the theater. Unlike a bridge, the chorus is not musically transitional, but makes a concluding statement for the song. The chorus, which contains the hook of the song, must stand out and contrast from the rest of the song. In other words, the music of the chorus is often placed higher in the scale to make it stand out and to spotlight the hook.
Writers often use a key change at the chorus to separate it and set it apart.
Lyrically, also, the rhyme pattern and even the cadence of the syllables can and should change at the chorus to define and emphasize it. The whole purpose of the Verse-Chorus Song is to call attention to the hook or the main idea. To do this effectively, the chorus must repeat several times throughout the song. Most commercial songs today contain at least two verses and two choruses with a possible third repetition of the chorus to conclude the song. It is extremely important that the verses are constructed in such a way that the chorus sounds like the inevitable and logical conclusion to each of the verses.