By 1971 you could put many components on a chip. Intel’s question was whether you could put a whole central processing unit on one. The answer, the Intel 4004, turned the computer from a cabinet of boards into a commodity part cheap enough to embed in almost anything.
The idea
Integrate the entire CPU, the arithmetic unit, registers, and control, onto a single chip. The processor stops being a machine you build and becomes a component you buy.
The 4004
Released on 15 November 1971, the Intel 4004 was the first commercial microprocessor, a complete CPU on one chip with about 2,300 transistors. It came together from Ted Hoff’s proposal for a simpler architecture, the design work of Stanley Mazor and Masatoshi Shima, and Federico Faggin’s silicon-gate implementation that fit it all onto a single die.
Why it changed everything
A CPU on a chip is cheap, small, and easy to embed. The same kind of part that ran a calculator could run a cash register, a car’s engine controller, or a personal computer. Computing escaped the machine room and spread into ordinary objects, which is the world we live in now.
The lineage
The microprocessor is the integrated circuit applied to the processor itself, and Moore’s law is why each new generation packed in more transistors and ran faster. The instruction-set stability that lets one software base survive across those generations is the idea the System/360 introduced.
Related Notes
- The Integrated Circuit, the technology the microprocessor is built from
- Von Neumann Architecture, the CPU model placed on the chip
- Moore’s Law, why microprocessors kept improving
- The IBM System/360, the instruction-set-as-contract idea
- History of Computing, the section index
Sources
- “Intel 4004,” Wikipedia. https://en.wikipedia.org/wiki/Intel_4004 . Supports the 4004’s release on 15 November 1971 as the first commercial microprocessor, a complete CPU on a single chip with about 2,300 transistors, designed by Faggin, Hoff, Mazor, and Shima.