The original Pokémon Red and Green games were released for the Game Boy.
Game Freak developed the role-playing games for Nintendo’s monochrome handheld system, using its link cable to support trading and battling between players. That communication feature became one of Pokémon’s defining ideas and helped distinguish the series from many other role-playing games.
The Japanese versions were titled Pocket Monsters Red and Green. Outside Japan, the first pair was released as Pokémon Red and Blue, using the revised Japanese Blue version as the basis for the international editions. The original Japanese Green version was not released internationally at that time.
Pokémon later appeared on the Game Boy Color, Game Boy Advance, Nintendo DS, and many newer systems. However, the 30th anniversary specifically looks back to the 1996 Game Boy debut, when Pokémon began as a handheld game built around collecting, training, battling, and trading.