what is Thrash metal?

Thrash metal is a subgenre of heavy metal music, one of the extreme metal subgenres that is characterised by its high speed and aggression.

The origins of thrash metal are generally traced to the late 1970s and early 1980s, when a number of bands began incorporating the sound of the New Wave of British Heavy Metal (creating a new genre and developing into a separate movement from punk rock.) This genre is much more aggressive compared to its relative, speed metal. There is often significant crossover from one metal category to another, and the influence of non-metal genres, including classical music and jazz, is not uncommon.

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