Black Sabbath, along with Deep Purple, were really the originators of Heavy rock, which was also called 'heavy metal' at the time. Later on "heavy metal" came to be applied to other things, but really Sabbath were the first. Deep purple are up there too, but I think Sabbath were the heaviest. Their best work was what they did with Ozzy, before he went off to the US to be a superstar. Once the band split, it was never the same, and I didn't think all that much of what Ozzy did in the US either, some of it was almost like a caricature of the real thing. These four songs are examples of the real thing.
