Gunpei Yokoi's inspiration for Nintendo's Game & Watch came from an unexpected source: observing a salaryman playing with a calculator on a train in 1979. This sparked the idea to bring games beyond arcades and home consoles to portable devices, fundamentally transforming Nintendo's trajectory. Yokoi's innovation established the company as a gaming leader and introduced design concepts—the clamshell format and D-pad—that remain industry standards to this day.

The Game & Watch technology cleverly repurposed calculator components, utilising LCD screens, button cell batteries and segment display systems. The first title, Game & Watch: Ball (1980), employed a 72-segment chip for its display. Between 1980 and 1991, Nintendo released 59 Game & Watch titles that collectively sold over 43 million units worldwide, underpinned by Yokoi's philosophy of "lateral thinking with withered technology"—finding innovative applications for existing, proven hardware—an approach that later influenced the hugely popular Game Boy and continues to shape Nintendo's product design philosophy today.