CRASH COURSE ON ALL METAL GENRES

Speed Metal is a subgenre of heavy metal that evolved out of the NWOBHM-derived sound that hit the shores of the United States between the late 1970s and early 1980s eras of metal, and was thus pioneered especially by mostly American heavy metal bands of the time. Speed metal is the predecessor to thrash metal, however speed metal is typically referred to as thrash metal in general because of its generally similar techniques, although this is technically not the case aesthetics-wise.

Characteristics
Like thrash, speed metal incorporated faster tempos and a greater emphasis on guitar playing a drumming. How it differs from thrash is largely due in part to its distinct emphasis on keeping with the melodic structure that was drawn from the sound coming from the NWOBHM influence while retaining fast-tempo songs and intense guitar riffing.

Speed metal can sometimes be musically similar to Power Metal