Eben Upton didn't plan on becoming a computer engineer. It happened out of necessity. The 38-year-old inventor of Raspberry Pi—the credit card-sized computer that costs less than a movie ticket—recalls a day from childhood when he tried to print a homework assignment. The words came out in a jumble, forcing him to learn how tweak the switches on the printer's circuit board to make the text fill the page. "It was just in accomplishing trivial tasks that we were having to acquire skills," he says of the experience.

Raspberry Pi offers far more accessibility than the TRS-80, Commodore 64, and early Apple and PC machines his generation worked with. But he hopes the bare bones computer he developed five years ago encourages a younger generation to discover how computers, smartphones and connected devices actually work.

As everything grows ever more computerized, the need to understand what lies beneath the software grows more pressing.

It helps that anyone can program one. If you can follow one of the many online coding tutorials, you can have it performing simple tasks out of the box. You'll find the Raspberry Pi in industrial machines and hobbyist projects alike. Schools use them in computer science classes. Do-it-yourselfers around the world have installed the diminutive computer in all manner of gadgets that do all manner of things.

The new low-power, low-cost Raspberry Pi Zero W updates the previous Zero computer board released a little more than a year ago. The "W" stands for wireless, because this Pi features built-in Bluetooth and Wi-Fi capabilities. The $10 price reflects Upton's business model (No VCs or shareholders to answer to!) and guiding principle: there's value in knowing how things work. As everything grows ever more computerized, he says, the need to understand what lies beneath the software grows more pressing.

"It's very dangerous to have a world in which people are completely divorced of technical underpinnings of the things around them," he says. "It's unsatisfying on an intellectual level that everything should just be like, 'A wizard did it.'"

Cheap Is the Thing

The Raspberry Pi, like the Arduino, provides an affordable and accessible entry to coding. It also offers innovators, inventors, and entrepreneurs the computing power for a growing number of connected devices. The bargain-basement price opens the internet of things to anyone with an idea and some basic coding skill.

Upton developed the Raspberry Pi five years ago as a teaching tool for undergraduate students in his computer science program at Cambridge University. He soon realized the little circuit board could be so much more. "We slotted into an empty market segment," he says. "We made the Raspberry Pi and people were like, 'Hey, that's the thing I couldn't describe but always wanted!'"

The computer cost just $25, yet offered surprisingly robust computing power. Tinkerers loved it, because it allowed them to experiment with hacking household devices and drew all kinds of people into developing hardware. "It turns into a disposable thing," says Will Hart, general manager at the connected device platform Particle. "If you fry it, it's like, 'Whatever.'"

Scott Kildall found Linux, the Pi's operating system, intimidating when started his residency at Autodesk's Pier 9 workshop in 2014. But he saw tremendous potential for his conceptual art, and so learned the ins and outs of the OS and started exploring the platform. Kildall, now the shop lead for the Pier 9 electronics lab, started posting his Raspberry Pi projects on Instructables.com, the online home for a wide swath of the maker movement. Three years later, the site teems with Raspberry Pi-powered creations.

Granted, you won't see any of Kildall's whimsical projects become the next big thing in IoT—his SelfiesBot is a portable robot outfitted with a 2-foot gooseneck arm that takes and posts selfies to Twitter. But the fact that non-scalable absurdist art can be equipped with computational capacities demonstrates the unexpected reach of Upton's creation.

Upton says tens of thousands of Raspberry Pis have just "disappeared" into products. The computer has become so ubiquitous that companies don't tout the fact their products use the little computers. But the Raspberry Pi's larger impact lies with the smaller-scale market. The computer designed to be an educational tool has brought the internet of things era to the masses. Anyone with the money to buy a burrito can bring a product to life.