![Photo of Robert Cornelius](https://www.historynet.com/wp-content/uploads/2022/10/Robert-Cornelius-AMHP-Winter-23-1.jpg)
Besides advancing the medium on a scientific plane, Robert Cornelius invented what may be the most common photo category ever. (Library of Congress)
Besides advancing the medium on a scientific plane, Robert Cornelius invented what may be the most common photo category ever.