How disinformation works—and how to counter it

These stories are, of course, all bogus. They are examples of disinformation: falsehoods that are intended to deceive. Such tall tales are being spread around the world by increasingly sophisticated campaigns. Whizzy artificial-intelligence (AI) tools and intricate networks of social-media accounts are being used to make and share eerily convincing photos, video and audio, confusing fact with fiction. In a year when half the world is holding elections, this is fuelling fears that technology will make disinformation impossible to fight, fatally undermining democracy. How worried should you be?