Hadouken is Ryu's signature fireball attack in Capcom's Street Fighter series, first introduced in the original arcade game in 1987 and made globally famous by Street Fighter II in 1991. Players perform it with a quarter-circle motion and a punch, and Ryu's shouted name for the move became one of gaming's most recognisable sounds. It spread beyond arcades through tournaments, cartoons, parodies and online memes, where the shout alone could signal a fight. It remains popular because it is short, instantly recognisable and instantly turns any clip into a playful battle moment.