Rock music originated in the 1950s as rock and roll developed from genres like blues and country music. It is characterized by electric guitars, bass guitar, and drums in a typical verse-chorus form. Conventions of rock music include song lengths of 5-8 minutes compared to the average pop song of 3 minutes. The genre has a large, primarily male audience aged 16-24. Key artists include Elvis Presley, The Rolling Stones, The Who, and albums like Elvis Presley's debut album and The Rolling Stones' Exile on Main St. Rock music is covered across media like radio stations, websites, and rock music festivals.