Americana is an amalgam of American folk music formed by the confluence of the shared and varied traditions that make up the musical ethos of the United States; specifically those sounds that are merged from folk, country, blues, rhythm and blues, rock and roll and other external influences. Americana, as defined by the Americana Music Association (AMA), is "contemporary music that incorporates elements of various American roots music styles, including country, roots-rock, folk, bluegrass, R&B and blues, resulting in a distinctive roots-oriented sound that lives in a world apart from the pure forms of the genres upon which it may draw. While acoustic instruments are often present and vital, Americana also often uses a full electric band."
Americana as a radio format developed during the 1990s as a reaction to the highly polished sound that defined the mainstream music of that decade (similar pressures also led to the formation of the classic country format at around the same time). The name and place for a new genre also arose in response to the lack of a format for the 1987 album "So Rebellious A Lover" by Gene Clark (Byrds) & Carla Olson (Textones). The album also featured Chris Hillman (Byrds, Burrito Brothers), Stephen McCarthy (Long Rydeers) and Randy Fuller (Bobby Fuller Four). In addition to original songs there were songs written by Woody Guthrie, Gram Parsons, Joe South and John Fogerty, The record was produced by Michael Huey (Joe South, Billy Joe Royal, Classics IV).
Because of listener interest in the artists who do not fit as comfortably in the country or rock genres, a radio format called "Americana" was developed by the AMA and reported by R&R (Radio & Records, a radio trade publication). Born out of Triple A, non-commercial, country and other formats, the Americana format is the sum of the parts that have showcased Americana music since its inception.