Pokémon Red and Green originally launched on the Game Boy in Japan.
The Game Boy was Nintendo’s monochrome handheld system, first released in 1989. Although it was already several years old by Pokémon’s debut, its large installed audience and relatively low cost helped the games reach a broad group of players.
Pokémon’s design was especially suited to portable play. Players could explore, battle, and trade, with the Game Boy Link Cable allowing two systems to connect. Trading was important because some Pokémon were exclusive to one version, encouraging players to interact with friends.
The games are often associated with the Game Boy Color because Pokémon Yellow used its color capabilities and later international play commonly took place on that hardware. However, Red and Green began as Game Boy titles, and their original Japanese release predates the Game Boy Color’s launch.