It-isn't just baseball fans that love them, the archetypal heavy metal band, Black Sabbath became almost a parody of themselves and a cornerstone of the genre, almost on a par with the mighty Led Zeppelin. Lead singer Ozzy Osbourne is now its most famous face, thanks to his own reality sitcom TV show, but remarkably the other founder members Tony Iommi, Terence 'Geezer' Butler and Bill Ward are still with the band though there have been countless shifts of personnel down the years.

The band began life as the 'Polka Tulk Blues Band' in the UK's Birmingham in 1968. Blues and hard rock was their forte, playing covers of Hendrix and Cream after switching names to the more meaty sounding 'Earth'. Bassist Butler, a fan of occult novels, wrote a song 'Black Sabbath' and, when Earth became confused with another similarly named band, it was adopted as the new moniker. Butler's fascination with horror also sparked the idea of cashing in on the 70s' craze for horror movies.

They became music's answer to 'Night of the Living Dead' - and with instant success, not least thanks to fearsome noise levels and Ozzy's wild stage antics. Their first album Black Sabbath and the follow-up Paranoid sold well in both the UK and US. A showbiz gloss on the occult and Butler's hammed up horror lyrics had set them apart. These Birmingham bozos were seriously off the wall, creating metalhead battle hymns on an epic scale.

The Black Sabbath trademark heavy, dark sound was literally an accident. A couple of Iommi's fingertips had been sheered off when he was still a mere sheet metal factory worker and it forced him to retune his guitar to lower the tension in the strings. Butler then retuned his bass guitar to match Iommi and a voila - a darker, heavier, sluggish sound emerged.

The band sounded so adolescently unhealthy it wasn't true. A third album Masters of Reality in 1971 was unusual for its acoustic material but the follow-up 'drugs' album Vol 4 almost chokes on its own excess, a theme to be repeated with the thumping heavy riffs and tortured lyrics of Sabbath Bloody Sabbath in 1973.

By now Black Sabbath was the biggest heavy metal band on the planet and their lifestyle went into predictable freefall with near suicidal intake of drugs and alcohol. The sleazy excess was reflected in management rows, and label changes. Despite the backstage damage they released the creditable Sabotage in 1975 but Technical Ecstasy the following year was a major disaster.

The burden of symphonic strings, synthesizers wasn't helped by Ward's vocals after Osbourne had walked out of the recording studio. After a 1977 tour Osbourne finally ditched the band and his last appearance on Never Say Die! in 1978 seemed to say just the opposite. Eventually Osbourne was thrown out and replaced by vocalist Ronnie James Dio.

The move sent Black Sabbath on a rollercoaster, with some of their best albums and their worst. It was a shot in the arm (not literally) at first with the 1975 album Heaven and Hell selling well. But that year's tour drug and booze-addled Ward quit and drummer Vinny Appice joined the band. Appice and Dio then walked out, Ward returned and singer Ian Gillan joined. It was musical chairs gone mad. A decent album Born Again came out of the reshuffle before Ward left again and members began to change almost weekly.

A couple of albums emerged from the endless shifting line-up before Black Sabbath was hit with management catastrophe and financial ruin. Despite a successful release of The Eternal Idol in 1987 the band broke up. Very like a baseball team really, you can be at the top of the world and fall back to ground so fast.

Over the year some of the more stable members have got back together with mixed results. While Headless Cross in 1988 was critically acclaimed, the awful Tyr was released the following year. Black Sabbath compilations tended to feature the Ozzy Osbourne glory years but, despite constant changes, they refuse to lie down and die. The band plays on and on (sometimes even with Osbourne back in the mix) oblivious of its ancient fan base and declining record sales.

Black Sabbath definitive album: Black Box: The Complete Original Black Sabbath (2004)

Black Sabbath best albums: Black Sabbath (1970), Paranoid (1971), Heaven And Hell (1980), Mob Rules (1981), Best of Black Sabbath (2000)

Black Sabbath missable albums: Technical Ecstasy(1976), Seventh Star (1986), Tyr (1990), Forbidden (1995)