In 1971, Intel which had been founded by Robert Noyce and Gordon Moore in Santa Clara, California in 1968, introduced a revolutionary new chip, the microprocessor. Its first application wold be in a new line of programmable electronic calculators. The first electronic calculator had been introduced in 1963 by a British company, Bell Punch, using discrete transistors, and about the size of a cash register. Four years later, Texas Instruments introduced a smaller version using logic ICs and two types of memory chips, RAMs for storing numbers entered by the user and calculated by the machine, and ROMs for holding the internal operations and for procedures like finding square roots. Followed were smaller and cheaper versions, and the slide rule, the utilitarian holdover from the seventeenth century became obsolete.

In the summer of 1969, Busicom, a Japanese calculator manufacturer asked Intel to develop a logic and memory chips which would increase the number of transistors per chip from one thousand to three or five thousand. Intel had developed a two thousand version. Intel assigned the Busicom job to Marcian E. Hoff, Jr., a thirty two year old engineer with a B.S. from Rensselaer Polytecnic Institute in Troy, New York, and a doctorate from

Stanford. Hoff studied the Busicom design and decided it was much too complicated to be cost effective. Rather than design a specific chip for a specific task, he proposed to design a general purpose logic chip which would serve as a central processor of a computer and could perform any logic task. The microprocessor would be programmable , taking its instructions from RAM and ROM. Programming a calculator, Intel would write a calculator program and insert it into ROM. Each calculator would only need one programmed ROM, one microprocessor and several other chips. Programming the ROM for a digital clock, would also serve in the same way and preclude the design of a new logic chip for each customer. Now the burden of the design would shift to the costumer with Intel doing a less costly and time-consuming programming for the ROM.

It was a brilliant idea. Busicom's calculator only need four chips, not twelve. The four were a microprocessor, a ROM, a RAM, and an input/output IC to relay user inputs and outputs. The microprocessor, a programmable processor on a chip, expands a device's capability and cuts its manufacturing costs. Busicom accepted Hoff's scheme, and the first microprocessor designated the 4004 was produced in late 1970s. In an agreement with Busicom, Intel decreased its price in exchange for the right to market the 4004.

How fortunate for Intel! No one grasp the importance of Hoff's invention which would go beyond calculators and minicomputers to be used in any control of a process. The 4004 would be replaced by the 8008, then the 8080 in 1974, and this would propel Intel a billion dollar company.