The counterculture was a youth movement that included political activism, especially in opposition to the Vietnam War, and the promotion of various hippie ideals. The hippies were associated primarily with two kinds of music: the folk-rock and country rock of people like Bob Dylan and Gram Parsons, and the psychedelic rock of bands like Jefferson Airplane and The Doors. This movement was very closely connected to the British Invasion, a wave of bands from the United Kingdom who became popular throughout much of the 1960s. The British Invasion initially included bands like the Beatles, the Rolling Stones, and The Zombies who were later joined by bands like the Moody Blues and The Who. The sound of these bands was hard-edged rock, with the Beatles originally known for songs that resembled classic black rock songs by Little Richard, Chuck Berry, Smokey Robinson, The Shirelles and the Isley Brothers. Later, as the counterculture developed, The Beatles began using more advanced techniques and unusual instruments, such as the sitar, as well as more original lyrics.