The famous 'rock on' hand gesture was actually a secret trick used by Ronnie James Dio’s grandmother to scare away bad luck and ward off the "evil eye."

In 1979, Ronnie James Dio joined the famous band Black Sabbath. He needed a cool signature move that was different from the 'peace' sign used by the previous singer, Ozzy Osbourne. Dio remembered his Italian grandmother making a specific hand sign called the 'mano cornuta' or 'horned hand.'In Italian culture, this gesture was used to ward off the 'Malocchio,' which means the 'evil eye.' People believed that if someone gave you a dirty look, it could bring bad luck or even sickness. Making the horns was a way to flip that bad energy away. Dio took this old protective charm and showed it to thousands of fans at his concerts.The gesture is made by holding down your two middle fingers with your thumb while keeping your pointer and pinky fingers straight up. Even though some people thought it looked scary or 'devilish,' Dio always said it was about protection and tradition. It quickly became a way for metal fans to identify each other and show they belonged to the same group.Today, this move is used all over the world at concerts and sporting events. It is one of the most famous examples of a 'subcultural signal,' which is a secret handshake or sign that helps a group feel like a big family. What started as a grandma's superstition is now the universal symbol for rocking out.