Some of the most famous and enduring songs from “the great American songbook” have been selected and edited especially for singers in this landmark series, with songs from George & Ira Gershwin, Richard Rodgers & Lorenz Hart, Jerome Kern, Cole Porter, Irving Berlin and many others. The music all dates from the 1920s to the early 1960s, in a musical style that pre-dates the rock era. The majority of the songs appear in all four volumes, though some songs are uniquely in the women's volumes or men's volumes. Unlike standard piano/vocal sheet music, the edition does not have the melody in the piano accompaniment, which gives the singer more vocal freedom. Keys have been carefully chosen for each voice type. Each volume also includes a historical note about each song, often citing recording artists who became associated with a song.