People in the 1950s listened to music primarily through radio, television, record albums, tapes, and live performances. The introduction of the vinyl LP record allowed for longer continuous play than previous formats. By the end of the 1950s, portable transistor radios became popular, allowing people to listen to music outdoors and in cars. Rock and roll dominated the decade with popular artists like Elvis Presley, Chuck Berry, and Pat Boone. Jazz artists such as Ray Charles, Ella Fitzgerald and Billie Holiday were also popular. Country music stars of the era included Hank Williams, Patsy Cline and Bill Monroe. The rise of rock-and-roll closely corresponded with the emergence of teenagers as a distinct social group with disposable