A look inside the algorithms that are shaping our lives and the dilemmas they bring with them.

If you were accused of a crime, would you rather have an impartial algorithm or an empathetic judge decide your sentence? This is just one of the dilemmas we face today, when the machine reigns supreme: telling us what to watch, where to go, even whom to send to jail. But as we rely on algorithms to automate big, important decisions—in crime, healthcare, transportation, and money—our reliance raises questions about what we want our world to look like. What matters most: Helping doctors with diagnosis or preserving privacy? Protecting victims or preventing innocents from being falsely accused? Hello World takes us on a tour through the good, the bad, and the downright ugly of the algorithms that surround us. With mathematician Hannah Fry as our guide, we’ll lift the lid on their inner workings, demonstrate their power, expose their limitations, and examine the ways that they can ultimately improve on the human systems they replace.