Hard-Rock

Hard rock is a variation of rock and roll music which has its earliest roots in mid-1960s garage and psychedelic rock. It is typified by a heavy use of distorted electric guitars, bass guitar and drums. The term "hard rock" is often used as an umbrella term for genres such as grunge or metal and in order to distinguish them from pop rock genre.
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Heavy metal (sometimes referred to simply as metal) is a genre of rock music that developed in the late 1960s and early 1970s. With roots in blues-rock and psychedelic rock, the bands that created heavy metal developed a thick, heavy, guitar-and-drums-centered sound, characterized by highly amplified distortion and fast guitar solos. The All Music Guide states that "of all rock & roll's myriad forms, heavy metal is the most extreme in terms of volume, machismo, and theatricality."
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