Nintendo Research & Development No. 1 Department (commonly abbreviated as Nintendo R&D1 and formerly known as Nintendo Research & Development Department before splitting in 1978) was a division of Nintendo, and is its oldest development team. Its creation coincided with Nintendo's entry into the video game industry, and the original R&D1 was headed by Gunpei Yokoi. The developer has created several notable Nintendo series such as Donkey Kong, Mario, and Metroid.
R&D1 developed the hugely successful Game Boy line, which was released in 1989. They developed some of the line's most popular games, such as Super Mario Land, and created the character of Wario.