It comes from 1838 and was taken by Louis Daguerre himself. He writes there were probably people wandering through this scene on that day, but if they didn’t stay still, the camera would have missed them. Only one man shows up. He is on the sidewalk down on the lower left of the photo.
To achieve this image, he exposed a chemically treated metal plate for ten minutes. Others were walking or riding in carriages down that busy street that day, but because they moved, they didn't show up. Only this guy stood still long enough — maybe to have his boots shined — to leave an image.
Other primitive forms of photography had preceded this picture by over a decade. But this anonymous shadowy man is the first human being to ever have his picture taken, totally unaware that he was making history that day.
Read the full story here.
http://www.npr.org/templates/story/story.php?storyId=130754296&ps=cprs