The rhapsody is regarded as one of Gershwin's most recognizable creations and as a key composition which defined the historical period known as the Jazz Age. "The Nation" has described Gershwin's piece as inaugurating a new era in America's musical history. The editors of the Cambridge Music Handbooks have posited that "the "Rhapsody in Blue" (1924) established Gershwin's reputation as a serious composer and has since become one of the most popular of all American concert works." The "American Heritage" magazine notes that the famous opening clarinet glissando has become as instantly recognizable to concert audiences as Beethoven's Fifth.