Game Freak developed Pokémon Red and Green, the games that launched the Pokémon series.
Game Freak began as a video game magazine created by Satoshi Tajiri and later became a development company co-founded by Tajiri and illustrator Ken Sugimori. The company officially incorporated in 1989, several years before Pokémon reached the Game Boy.
For Pokémon, Tajiri directed the project, Sugimori handled much of the visual design, and Junichi Masuda composed the music and sound effects. Nintendo published the games, but publishing and development were separate roles. This distinction is a common source of confusion because Nintendo became the most visible corporate name associated with Pokémon.
Game Freak continued developing the core Pokémon role-playing games across later generations. Creatures and Nintendo also became important partners in the broader property, but Game Freak remains the studio most directly associated with the mainline game development that began in 1996.