Hard rock Styx helped further cement heavy rock in the Midwest as a form of stadium rock. In 1978, Van Halen emerged from the Los Angeles music scene with a sound based around the skills of lead guitarist Eddie Van Halen. He popularised a guitar-playing technique of two-handed hammer-ons and pull-offs called tapping, showcased on the song "Eruption" from the album "Van Halen", which was highly influential in re-establishing hard rock as a popular genre after the punk and disco explosion, while also redefining and elevating the role of electric guitar. The opening years of the 1980s saw a number of changes
Hard rock heavy metal sound. The same month, Steppenwolf released its self-titled debut album, including "Born to Be Wild", which contained the first lyrical reference to heavy metal and helped popularise the style when it was used in the film "Easy Rider" (1969). Iron Butterfly's "In-A-Gadda-Da-Vida" (1968), with its 17-minute-long title track, using organs and with a lengthy drum solo, also prefigured later elements of the sound. By the end of the decade a distinct genre of hard rock was emerging with bands like Led Zeppelin, who mixed the music of early rock bands with a more hard-edged form of blues rock