Masatoshi Shima, Japanese computer scientist and engineer, co-designed the Intel 4004

Masatoshi Shima is a Japanese electronics engineer. He was one of the architects of the world's first microprocessor, the Intel 4004. In 1968, Shima worked for Busicom in Japan, and did the logic design for a specialized CPU to be translated into three-chip custom chips. In 1969, he worked with Intel's Ted Hoff and Stanley Mazor to reduce the three-chip Busicom proposal into a one-chip architecture. In 1970, that architecture was transformed into a silicon chip, the Intel 4004, by Federico Faggin, with Shima's assistance in logic design.

The Intel 4004 was part of the 4 chip MCS-4 micro computer set, released by the Intel Corporation in November 1971; the 4004 being part of the first commercially marketed microprocessor chipset, and the first in a long line of Intel central processing units (CPUs). Priced at US$60, the chip marked both a technological and economic milestone in computing.