Speed metal is a sub-genre o hivy metal that originated in the early 1980s frae NWOBHM an hardcore punk roots. It is described bi Allmusic as "extremely fast, abrasive, an technically demanding" muisic.
Motorhead is aften creditit as the first baund to invent/play speed metal. Ither hivy metal baunds, like Judas Priest an Iron Maiden, haed significant influence on the genre. This can inspecially be haurd in their duelin guitar soond, that wad come tae be a staple o speed metal. Some o speed metal's earlier influences include Queen's "Stone Cold Crazy" (that wis eventually covered bi the thrash metal baund Metallica), frae their 1974 album Sheer Heart Attack, an Deep Purple's sang "Highway Star", frae their album Machine Head. The latter wis cawed 'early speed metal' bi Robb Reiner of speed metal band Anvil.
Speed metal eventually evolved intae thrash metal. Though a feck o fowk tend tae equate the twa subgenres, there a distinct differ atween the twa. In his book "Sound of the Beast: The Complete Headbanging History of Heavy Metal", Ian Christe states that "...thrash metal relies mair on lang, wrenching rhythmic breaks, while speed metal... is a cleaner an mair muisically intricate subcategory, still lyal tae the duelin melodies o classic metal."