"Computer vision" has a decidedly sci-fi ring, so it's no surprise the idea of smart devices becoming all-seeing tools has captured people's imaginations. Yet the true potential of the tech is held back by a widespread misunderstanding of what great applications look like and what they can achieve. Where did computer vision come from? It's the product of a proliferation of cheap, high-quality cameras, which has expanded the scope for imagery captured in public, private, and commercial domains. At the same time, advances in machine learning and deep learning technology are allowing us to transform those images into digital signals that support a wide range of actions.