Pikachu first appeared in Pokémon Red and Green in Japan in 1996 before becoming the face of the franchise through the long-running anime series that began in 1997. Voiced in the anime by Ikue Ōtani, Pikachu communicates almost entirely by repeating variations of its own name, and the cheerful pika pika sound became one of the most recognisable character cries in pop culture. As Pokémon games, films and online clips spread worldwide, creators began reusing the short cry as a reaction sound for cute, surprising or nostalgic moments, keeping it popular across generations of fans.