Yokoi started work for Nintendo in 1965 as an assembly-line repairman. In his spare time, he would build electronic toys. In 1966 the then president of Nintendo took notice and assigned him the job of inventing more such toys until in 1974 the company decided to make video games.
Yokoi was put in charge of the development team known as Nintendo Research and Development 1 or R&D1. There He produced Metroid and designed the Game Boy, and worked with Shigeru Miyamoto on Donkey Kong and Mario Bros. He left Nintendo in 1996 to form his own company called Koto approximately a year before his death in 1997.
Yokoi is known for the concept of “Lateral thinking” which involves thinking of new uses for existing technology. At Nintendo, he used this way of thinking extensively, rather than create ultra-expensive electronics he would look for existing technology that was reliable and cheap to manufacture then figure out how to do new and exciting things with it. This idea continues to be employed at Nintendo, an example of this is the Wii, with internal technology similar to the GameCube and not as advanced as the Xbox 360 or PS3 but still managed to compete by introducing a new style of game play.
Contributions to the Tessera: With S continually trying to destroy the order’s inventions Yokoi’s “Lateral thinking” help him and other Tessera members’ designs become more reliable and easier to fix/replace in the wake of S’s destructive path.
“Gunpei Yokoi.” Wikipedia, Wikimedia Foundation, 26 Oct. 2017, en.wikipedia.org/wiki/Gunpei_Yokoi.