American popular music had a profound effect on music across the world. The country has seen the rise of popular styles that have had a significant influence on global culture, including ragtime, blues, jazz, rock, R&B, doo wop, gospel, soul, funk, heavy metal, punk, disco, house, techno, salsa, grunge and hip hop. In addition, the American music industry is quite diverse, supporting a number of regional styles like zydeco, klezmer and slack-key. The appeal of these styles lies in their supple, energetic rhythms, their appealing vocal lines, and in many cases their symbolic associations with the plight of the underprivileged.

Distinctive styles of American popular music emerged early in the 19th century, and in the 20th century the American music industry developed a series of new forms of music, using elements of blues and other genres of American folk music. These popular styles included country, R&B, jazz and rock. The 1960s and '70s saw a number of important changes in American popular music, including the development of a number of new styles, including heavy metal, punk, soul, and hip hop. Though these styles were not popular in the sense of mainstream, they were commercially recorded and are thus examples of popular music as opposed to folk or classical music.

Source: Wikipedia