Despite being branded as autonomous and self-sustaining, artificial intelligence relies heavily on human labor — an army of data workers all over the world, primarily in the Global South. These workers “are purposely hidden by the companies that produce AI because they are the secret ingredient of AI itself,” says sociologist Antonio Casilli, the author of Waiting for Robots: The Hired Hands of Automation and co-writer of the documentary In the Belly of AI. Casilli estimates that over 160 million people are involved in data work around the world.