BBC News is reporting:

American rock singer RONNIE JAMES DIO (DIO, BLACK SABBATH, HEAVEN & HELL, RAINBOW, ELF), who died on Sunday, popularised a hand gesture commonly used by heavy metal fans. But what does it mean?

It's a gesture commonly seen at rock concerts.

The index finger and the little finger are upright and the thumb is clasped against the two middle fingers.

Ronnie James Dio, who sang with Black Sabbath and Rainbow before forming his own band, was partly responsible for it becoming a common symbol among metal fans.

But it has other uses too, depending on the position of the thumb, and the context. Here is a round-up of some of the common meanings.

"Ronnie started throwing the horns shortly after replacing Ozzy Osbourne as Black Sabbath's vocalist in 1979," says Simon Young, news editor of heavy metal magazine Kerrang!.

"Many metal fans began to reciprocate the gesture and along with headbanging, it became synonymous with metal."

Dio wasn't the first, says Young. In the 1960s, there had been COVEN frontman Jinx Dawson, and the cartoon version of John Lennon on the cover of THE BEATLES' Yellow Submarine was seen using it too. But it really took off from Dio.

It has been misinterpreted as a sign of allegiance to the devil, because the shape of the fingers have been associated with 666, the number of the beast, says Young.

But Dio, says Young, explained that he was taught the so-called corna sign by his Italian grandmother, as a way to scare off the "evil eye", a look which is said to cause bad luck. It's like knocking on wood for superstitious purposes

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