What if specially engineered shoes could fend off mosquitoes or a tractor-sharing app could put money in Nigerian farmers’ pockets? These are just two of the questions innovators were bold enough to ask—and answer—this year. They taught a new generation of robots to perform millions of tasks. They mixed carbon dioxide and sunshine to make cheap, clean fuel. And in just 15 hours, they fashioned a device that can convert printed words to Braille. Collectively, these thinkers asked one fundamental question: What does the world need next?