Pop music is also known as popular music and includes a large number of genres and styles. In America, pop music is an important aspect of U.S. culture, even though it is primarily a form of entertainment. The most popular pop songs are ranked on the Billboard list as Top 40 hits.
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Origins
• Pop music existed since America's early years, primarily as parlor songs and minstrel show tunes. Tin Pan Alley, ragtime and Broadway music are the earliest forms of American pop, but the first recorded pop music in America came in the early 1900s on phonographs of barbershop quartets and vaudeville performances. Popular jazz and blues were the pop music of the American 1920s through the 1940s.

Black Music
• What started as communal singing within black culture often became popular music. Both jazz and blues genres were forms of black music, originating in Southern areas such as New Orleans, but popularized in Northern cities such as Chicago and New York. Similarly, hip hop is a modern form of black music that developed within urban communities of poets and artists, eventually becoming commercialized through major record labels.
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Country
• Folk music existed in America since the country's inception, with patriotic songs and mountain music. It wasn't until the 1920s that country music became a popular genre. Artists such as the Carter Family were prominent in this time, often receiving play on radio stations. This music inspired musicians such as Hank Williams, Johnny Cash and even Elvis Presley, all of whom are American pop music legends.

Rock
• Through the combination of black music and country music came rock and roll. Chuck Berry and Elvis Presley popularized rock music, and the genre went on to evolve until the end of the century. Artists such as Bob Dylan and the Beach Boys led the '60s, until even more diversified music became popular in the '70s and '80s with hard rock, disco, punk and contemporary Christian music (gospel). By the '90s, alternative music ushered in a highly produced era of pop music.

21st Century
• The pop music industry took a financial hit near the turn of the century because of the capability the Internet offered regarding music downloads. Indie music became increasingly prominent in pop music, with artists such as Arcade Fire and Death Cab for Cutie becoming top-sellers in both albums and concert sales.
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