November 15, 1971: Intel Launches the 4004 — the Microprocessor That Invisibly Runs Everything

On November 15, 1971, a tiny advertisement appeared in Electronic News announcing a new product from a young company called Intel: the 4004, a “micro-programmable computer on a chip” priced at $60. It was the world’s first commercially available microprocessor — a complete central processing unit etched onto a fingernail-sized piece of silicon. The digital age’s hidden engine had arrived.

Built for a Japanese Calculator

The 4004 was born of a contract, not a vision. Intel, founded in 1968 by Gordon Moore and Robert Noyce, had agreed to build twelve custom chips for Busicom, a Japanese calculator maker. Engineer Federico Faggin, Ted Hoff and Stan Mazor proposed something bolder instead: one programmable chip that could do all twelve chips’ jobs. Busicom accepted, got the calculators, and — in a deal that became Silicon Valley legend — gave Intel the rights to sell the chip to anyone. The 4004 ran at 740 kilohertz and executed 92,000 instructions per second. It was, by modern standards, hopelessly weak. Its architecture, though, was immortal: fetch, decode, execute — the same cycle that runs every computer on Earth.

The Engine Inside Everything

Intel’s 8008 and 8080 followed within three years; the 8086 (1978) launched the x86 dynasty that still powers most PCs and servers (see our IBM PC article of August 12). But the microprocessor’s real conquest was invisible: it left the computer room and colonized the world — cars, washing machines, elevators, heart pacemakers, spacecraft, and ultimately the billions of chips in phones and smart devices that run modern civilization. The 4004’s direct descendants number in the tens of billions; there are more microprocessors on Earth than people, by an order of magnitude.

The $60 Chip That Ate the World

Federico Faggin later called the microprocessor “the most important invention of the 20th century” — a claim hard to dispute, since Moore’s Law, Silicon Valley and the personal computer all rest upon it. Intel became one of the most valuable companies in history, its processors the brains of the digital revolution. Fifty-five years after that half-page ad in a trade newspaper, November 15, 1971 stands as the quietest big bang in technology: the day computation became a component, and the world became programmable.