This meant that musical fads, such as Hawaiian slack-key guitar, never died out completely, since a broad range of rhythms, instruments, and vocal stylings were incorporated into disparate popular genres. By the 1950s, forms of roots music had led to pop-oriented forms. Folk musicians like the Kingston Trio, blues-derived rock and roll and rockabilly, pop-gospel, doo wop and R&B (later secularized further as soul music) and the Nashville sound in country music all modernized and expanded the musical palette of the country. The roots approach to music emphasizes the diversity of American musical traditions, the genealogy of creative lineages and communities, and the innovative contributions of musicians working in these traditions today. In recent years roots music has been the focus of popular media programs such as Garrison Keillor's public radio program, A Prairie Home Companion and the feature film by the same name. Regional forms American traditional music is also called roots music. Roots music is a broad category of music including bluegrass, country music, gospel, old time music, jug bands, Appalachian folk, blues, Cajun and Native American music. The music is considered American either because it is native to the United States or because it developed there, out of foreign origins, to such a degree that it struck musicologists as something distinctly new. It is considered "roots music" because it served as the basis of music later developed in the United States, including rock and roll, contemporary folk music, rhythm and blues, and jazz. Appalachian music Appalachian music is the traditional music of the region of Appalachia in the Eastern United States. It derives from various European and African influences—including English ballads, Irish and Scottish traditional music (especially fiddle music), hymns, and African-American blues. First recorded in the 1920s, Appalachian musicians were a key influence on the early development of Old-time music, country music, and bluegrass, and were an important part of the American folk music revival. Instruments typically used to perform Appalachian music include the banjo, American fiddle, fretted dulcimer, and guitar. Early recorded Appalachian musicians include Fiddlin' John Carson, Henry Whitter, Bascom Lamar Lunsford, the Carter Family, Clarence Ashley, Frank Proffitt, and Dock Boggs, all of whom were initially recorded in the 1920s and 1930s. Several Appalachian musicians obtained renown during the folk revival of the 1950s and 1960s, including Jean Ritchie, Roscoe Holcomb, Ola Belle Reed, Lily May Ledford, and Doc Watson. The Carter Family