Every person’s face is unique. We intuitively know that to be true. But what exactly makes your face different from another person? And how can we measure and quantify that difference to make the world more accessible for the visually impaired? In this episode, journalist Shaun Raviv tells us how he uncovered the top secret history of facial recognition technology and its inventor, Woody Bledsoe. Then Karthik Kannan explains how a conversation with a group of visually impaired students inspired him to build glasses that can recognize human faces.