The big picture: Intel forever changed the trajectory of computing - and really, human history - with the introduction of the first commercially available microprocessor. The Intel 4004 launched 50 years ago to the day, on November 15, 1971, but it all started a couple of year earlier when Japan-based Nippon Calculating Machine Corp. asked Intel to design a set of integrated circuits for a prototype calculator called the Busicom 141-PF.

As Intel recounts, the original plans called for a dozen custom chips but the company's engineers managed to adapt the design into just four chips including the 4004 central processing unit (CPU).

Up to that point, one needed room-sized computers to achieve similar levels of processing power.

The Intel 4004 was a 4-bit chip built on a 10 µm node. It packed 2,300 transistors and operated at a clock speed of 740KHz. FOr comparison, a modern CPU can contain billions of transistors and trillions of operations per second.

Intel Senior Fellow Genevieve Bell said it's really a story about shrinking things. "And as you shrink them, you increase the potential of the places that they can go and the things that they can pass," Bell added.

Related Reading: The History of the Microprocessor and the Personal Computer

Stan Mazor, co-inventor of the Intel 4004, said its design was so revolutionary that it took roughly five years for Intel to educate engineers on how exactly to build new products based on microprocessors.

Even still, the direction of progress hasn't always been clear. "The capabilities of, for example, having a microprocessor of incredible capacity as a hearing aid, was not obvious in 1971," Faggin said.

Something else Faggin didn't see coming was the speed with which microprocessors developed over time and were adopted by the industry. It's hard to fathom a world without them today, and with the ongoing chip shortage, we're appreciating their presence more than ever.