For more than 800 years, the city of Cambridge has been associated with educational excellence. Sir Isaac Newton, Charles Darwin, Stephen Hawking, Sylvia Plath and 15 British Prime Ministers are just some of the brilliant minds who have studied at the city's university.

Today, the Raspberry Pi, a credit-card sized computer developed by academics at the university, is helping to nurture the next generation of bright sparks by giving them an early taste of computer programming.

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The Raspberry Pi runs the free operating system Linux from an SD card, and is powered by a USB charger. To run the Raspberry Pi, users plug in a mouse and keyboard to their device and then connect it to a TV or monitor. They can then start to learn programming skills.

"No one is surprised that you can build a cell phone for some tens of dollars," Eben Upton, a Raspberry Pi founder and CEO of Raspberry Pi's engineering team, told Innovation Cities.

"What we've really done with Raspberry Pi is to take that same cell phone technology that enables low cost computing and to package it in the form of an educational microcomputer," he added.

According to Upton, the Raspberry Pi was conceived as a response to the dearth of computer science undergraduates with, "an instinctive understanding of how computers work."

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The ethos behind the computer is one of accessibility - hence the low price - and encouraging potential.

"Our mission... is to give every child the opportunity to do a little computer programming, the opportunity to discover whether they have an aptitude for computing, and if they have that aptitude, an opportunity to develop it," Upton said.

Costing $35 or $25 depending on what model you buy, the Raspberry Pi has been a success since its launch in 2012. To date, more than 3.5 million have been sold.

The popularity of the Pi has not been restricted to the developed world either. In Africa, Raspberry Pis have been introduced to communities in Togo, Cameroon, Kenya and Nigeria.

Back in the U.K., earlier this month a 'Cambridge Jam' was held in the city, giving Raspberry Pi users young and old a chance to meet one another and take part in software, hardware and programming workshops using their Pi.

"There's a group of children who are really interested in computers," Michael Horne, who helps to run the Cambridge Jam, said. "They want to know how they work, and hopefully in the future they'll be the ones creating the new devices that the next generation will be using."

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It is early days, but Upton is hopeful that the Raspberry Pi can help to unearth computing's next big thing. "If you look at people like Bill Gates and Mark Zuckerberg, what they have in common is they all had some early experience with computing," he said.

"We very much hope some of the next generation... will be people who cut their teeth on the Raspberry Pi," he added.

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