What device feature inspired Pokémon's trading system?

The Game Link Cable inspired Pokémon's trading system. Satoshi Tajiri saw the communication feature of the Game Boy and imagined creatures moving between connected systems.

The cable allowed two Game Boys to communicate directly. In Pokémon Red and Green, players could battle or trade Pokémon by connecting compatible cartridges. This made the games deliberately interdependent: some species appeared in one version but not the other, encouraging players to meet and exchange Pokémon.

The idea grew from Tajiri's childhood interest in collecting insects. He wanted players to experience the excitement of finding, collecting, and sharing creatures, while also giving the Game Boy a social use beyond single-player play. The cable transformed a hardware accessory into a defining game mechanic.

The original system was wired, so players had to be physically close and use compatible equipment. Later Pokémon titles introduced wireless communication, internet trading, and online battles, but the basic principle remained the same: connection between players expands what each person can collect.