What was the name of the British rock band who had a significant influence on the development of heavy metal?

Black Sabbath were an English rock band formed in Birmingham in 1968 by guitarist Tony Iommi, drummer Bill Ward, bassist Geezer Butler and vocalist Ozzy Osbourne. They are often cited as pioneers of heavy metal music. The band helped define the genre with releases such as Black Sabbath (1970), Paranoid (1970), and Master of Reality (1971). The band had multiple line-up changes following Osbourne's departure in 1979, with Iommi being the only constant member throughout its history.

Black Sabbath have sold over 70 million records worldwide as of 2013, making them one of the most commercially successful heavy metal bands. They were ranked by MTV as the "Greatest Metal Band" of all time, and placed second in VH1's "100 Greatest Artists of Hard Rock" list. Rolling Stone magazine ranked them number 85 on their "100 Greatest Artists of All Time". Black Sabbath were inducted into the UK Music Hall of Fame in 2005 and the Rock and Roll Hall of Fame in 2006. They have also won two Grammy Awards for Best Metal Performance, and in 2019 the band were presented a Grammy Lifetime Achievement Award.