Installing Windows might take 5,000 years without the compiler, a remarkable innovation which made modern computing possible. Tim Harford tells a compelling story which has at its heart a pioneering woman called Grace Hopper who – along the way – single-handedly invented the idea of open source software too.

The compiler evolved into COBOL – one of the first computer languages – and led to the distinction between hardware and software.

Producer: Ben Crighton

(Image: Grace M. Hopper, Credit: Bettman/Getty Images)

Transferring money by text message is far safer and more convenient than cash. M-Pesa, as it is known, first took off in Kenya. The idea was to make it easier for small businesses to repay micro-finance loans. But, almost immediately, M-Pesa exploded into something far bigger - there are now 100 times more M-Pesa kiosks than ATMs in Kenya – and with far-reaching consequences, in many developing economies. Tim Harford describes how money transferred this way is easy to trace, which is bad news for the corrupt. And good news for tax authorities.

Producer: Ben Crighton

(Photo: Mobile Phone and M-Pesa sign, Credit: AFP/Getty Images)

Once too precious to use, now too cheap to notice – the significance of the lightbulb is profound. Imagine a hard week’s work gathering and chopping wood, ten hours a day for six days. Those 60 hours of work would produce light equivalent to one modern bulb shining for just 54 minutes. The invention of tallow candles made life a little easier. If you spent a whole week making them – unpleasant work – you would have enough to burn one for two hours and twenty minutes every evening for a year. Every subsequent technology was expensive, and labour-intensive. And none produced a strong, steady light. Then, as Tim Harford explains, Thomas Edison came along with the lightbulb and changed everything, turning our economy into one where we can work whenever we want to.

Producer: Ben Crighton

(Photo: Electric lightbulb, Credit: Science photo library)

Warrior monks, crusaders and the mysterious origins of modern banking. You might think banks are so central to every economy that they have always existed. And they have, sort of. But the true story of the origins of modern banking is – as Tim Harford explains – as surprising and mysterious as the plot of Dan Brown’s Da Vinci Code.

(Photo: Temple Church in London. Credit: Kiev Victor/Shutterstock)

How vast mega-stores emerged with the help of a design originally drawn in the sand in 1948 by Joseph Woodland as he sat on a Florida beach, observing the furrows left behind, an idea came to him which would – eventually – become the barcode. This now ubiquitous stamp, found on virtually every product, was designed to make it easier for retailers to automate the process of recording sales. But, as Tim Harford explains, its impact would prove to be far greater than that. The barcode changed the balance of power between large and small retailers.

(Image: Barcode with red laser line, Credit: Jamie Cross/Shutterstock)

Surprisingly, Uncle Sam played an essential role in the creation and development of the iPhone - of course, much has been written about the late Steve Jobs and other leading figures at Apple and their role in making the modern icon, and its subsequent impact on our lives. And rightfully so. But who are other key players without whom the iPhone might have been little more than an expensive toy? Tim Harford tells the story of how the iPhone became a truly revolutionary technology.

(Photo: Steve Jobs unveils the iPhone, Credit: AFP/Getty Images)

It's improved health, school attendance, agricultural productivity and farm worker wages, but concrete has a poor reputation. It takes a lot of energy to produce and releases a great deal of CO2 in the process. However, architects appreciate its versatility and there are few more important inventions. Tim Harford tells the remarkable hidden story of a ubiquitous, unloved material.

(Image: Masons hands spread concrete, Credit: APGuide/Shutterstock)

The boom in global trade was caused by a simple steel box. Shipping goods around the world was – for many centuries – expensive, risky and time-consuming. But, as Tim Harford explains, 60 years ago the trucking entrepreneur Malcolm McLean changed all that by selling the idea of container shipping to the US military. Against huge odds he managed to turn 'containerisation' from a seemingly impractical idea into a massive industry – one that slashed the cost of transporting goods internationally and provoked a boom in global trade.

Producer: Ben Crighton

(Photo: Container ship travelling along the Suez Canal, Credit: Science Photo Library)

Saving lives with thin air - by taking nitrogen from the air to make fertiliser, the Haber-Bosch Process has been called the greatest invention of the 20th Century – and without it almost half the world’s population would not be alive today. Tim Harford tells the story of two German chemists, Fritz Haber and Carl Bosch, figured out a way to use nitrogen from the air to make ammonia, which makes fertiliser. It was like alchemy; 'Brot aus Luft', as Germans put it, 'Bread from air'.

Haber and Bosch both received a Nobel prize for their invention. But Haber’s place in history is controversial – he is also considered the 'father of chemical warfare' for his years of work developing and weaponising chlorine and other poisonous gases during World War One.

Producer: Ben Crighton

(Photo: A farmer sprays fertiliser. Credit: Remy Gabalda/Getty Images)

Rudolf Diesel died in mysterious circumstances before he was able to capitalise on his extraordinary invention: the eponymous engine that powers much of the world today. Before Diesel invented his engine in 1892, as Tim Harford explains, the industrial landscape was very different. Urban transport depended on horses and steam supplied power for trains and factories. Incredibly, Diesel’s first attempt at a working engine was more than twice as efficient as other engines which ran on petrol and gas, and he continued to improve it. Indeed, it wasn’t long before it became the backbone of the industrial revolution; used in trains, power stations, factories and container ships.

Producer: Ben Crighton

(Image: Stamp depicting Rudolf Diesel, Credit: Boris15/Shutterstock)