There is a place on the internet where almost two billion of us regularly go – many of us, every day. Facebook: the social network which Mark Zuckerberg started in his university dorm room and which has grown, in a little over a decade, into one of the most valuable companies in the world. But what does Facebook’s lines of computer code do with the data we give it – and what could it do in the future? Just how powerful is Facebook's algorithm? The answer will surprise you.

Produced by Estelle Doyle and Sarah Shebbeare This programme was first broadcast in April 2017.

(Facebook CEO Mark Zuckerberg delivers a keynote address during Facebook's F8 conference in San Francisco, California. Credit: Getty Images)

Forty-two Americans die every day from an overdose involving painkilling prescription opioids. President Donald Trump recently declared the US opioid epidemic a national public health emergency. Yet in the world’s poorest countries, cancer patients and people recovering from major surgery often get no effective pain relief at all. Why is access to prescription painkillers so unequal? And is the shortage of opioids in much of the world getting the attention it deserves?

(Photo: View of poppies in a poppy field in the state of Guerrero, Mexico. Credit: Pedro Pardo/Getty Images)

Missiles, fighter jets and mines waiting on the sea bed - war games in the gulf. Tension between Iran and Saudi Arabia is at an unprecedented level since a missile was intercepted over Saudi Arabia’s capital city. The Saudi Crown Prince blames Iran and says the attack may be considered an act of war. This is what would happen if they did go to war.

(Photo: An Iranian missile is test-launched during war games in Qom, south of Tehran. Credit: Shaigan/Getty Images)

The world’s most profitable company is accused of aggressively dodging tax. Leaked documents in the Paradise Papers show Apple moved hundreds of billions of dollars in untaxed foreign profits to Jersey, where foreign companies pay no corporation tax. Yet Apple says it pays “every dollar it owes in every country around the world”. Confused? Not for long.

(Customers wait in front of the giant Apple logo for the store to open in Munich, Germany. Photo Credit: Christof Stache/GettyImages)

He’s pushed through reforms but some fear there is a darker desire driving the ruler. In one night, Crown Prince Mohammad bin Salman arrested over a dozen Princes and government ministers on corruption charges. To turn on his own royal family, he must be serious. But is corruption the Crown Prince’s real target or is this a power grab? There are also fears that the aggressive stance he has taken with Lebanon, Yemen and Qatar is increasing tensions with regional rival Iran. If the tension reaches a tipping point, there are fears the conflict could widen beyond the region. So what is he up to? What does the Saudi Crown Prince want?

(Photo: Saudi Crown Prince Mohammed bin Salman, in Riyadh on October 24 2017. Credit: Fayez Nureldine/Getty Images)

Academic research stands accused of turning a blind eye to dodgy data, failing to reconcile contradictory findings and valuing money over knowledge. We examine the criticisms, which go the very heart of our pursuit of knowledge.

(Photo: Scientist working in a research laboratory. Credit: Shutterstock)

The growth and reach of a group labelled a ‘terror force’ by President Trump. On 13 October President Trump announced new sanctions against Iran’s Islamic Revolutionary Guard Corp for supporting terrorism. But what is the Revolutionary Guard and what is its role in Iran and the Middle East?

The group started as an army to protect the values of the Iranian revolution of 1979, but their role in fighting a long and brutal war with Iraq strengthened their military clout considerably. Today their forces work beyond their borders and have played a key role in the fight against so-called Islamic State. But they are no longer just an army, they run construction projects, run most of the telecommunications industry and even have a news agency. So how powerful is the Islamic Revolutionary Guard Corps?

Presenter: Ruth Alexander Producers: Phoebe Keane and Jo Casserly

(Photo: Iran's elite Revolutionary Guard special forces participating in military manoeuvers. Credit: Getty Images)

Why internal conflicts end and what it might mean for Syria. The war in Syria is in its seventh year and there are few signs that an end is in sight. Yet over the years, other seemingly intractable civil conflicts have, eventually, been resolved. So, how did they do it and what lessons are there that might help Syria?

(A Kurdish Syrian woman walks with her child past the ruins of the town of Kobane in northern Syria. Credit: Yasin Akgul/Getty Images)

The head of the Roman Catholic Church has been accused of aiding the spread of heresy. A petition criticising the ambiguity of Pope Francis' statements on the treatment of people who have divorced and remarried is the latest twist in a fierce debate which is dividing Roman Catholics. The argument centres on whether divorcees on their second marriages should be able to receive Holy Communion, a ceremony that is central to the Christian faith. However, the dispute goes much deeper than that. At its heart, it is an argument over what it means to be a Roman Catholic and what the role of the Pope, and the Church, should be.

Presenter: Ruth Alexander Producer: James Fletcher and Helen Grady

(Photo: Pope Francis waves to thousands of followers in Manila, Philippines. Credit: Lisa Maree Williams/Getty Images)

From driverless cars to "carebots", machines are entering the realm of right and wrong. Should an autonomous vehicle prioritise the lives of its passengers over pedestrians? Should a robot caring for an elderly woman respect her right to life ahead of her right to make her own decisions? And who gets to decide? The challenges facing artificial intelligence are not just technical, but moral - and raise hard questions about what it means to be human.

(image: PaPeRo communication robot at the Robodex trade show in Tokyo, Japan, 18 January 2017. Photo credit: Tomohiro Ohsumi/Getty Images)

We all do it: ask a search engine things we wouldn’t dare ask a friend, post our lives on social media, hit the ‘agree’ button on privacy conditions we never read. This is life in our online age. To get our favourite apps and services for free, we provide companies with the intimate details of our lives. Businesses we’ve heard of, and many we haven’t, make money off this data in ways we may not fully realise. And almost every week it seems there’s another data breech – Equifax, Sonic, and Deloitte have been hacked in the last month alone. Each time the private data of millions of people is compromised. Can we control who knows what about us? And are we comfortable with how much information we’re giving up and how it might be used, or mis-used? This week the Inquiry asks “Is Privacy Dead?”

(image: Shutterstock)

The list of nations legislating to ban the sale of petrol and diesel cars is growing. But these restrictions won’t come into effect for decades. Air pollution contributes to thousands of early deaths each year and the scandal known as Dieselgate, when vehicle manufacturers admitted tampering with emissions tests, made us more aware of the polluting power of the diesel engine. Automotive technology is advancing quickly, but will greener vehicles really replace the combustion engine? Hybrid and electric cars are better for the environment but more expensive, and petrol stations are easier to find than charging points.

This edition of the Inquiry asks, if we wanted to, could we ban the sale of diesel and petrol cars now?

(image: Cars sit in gridlock in heavy fog (pollution) in Beijing China. Photo Credit: Guang Niu/Getty Images)