The plate is exposed to light. Wherever the light stuck the plate, the bitumen hardened and the extra was dissolved. What was left was the photo. But the first patent for photography in America was given to Alexander Wolcott in 1840 for his camera. In 1885, any one was able to own a camera after the Kodak was made. It was a simple camera and had to be sent back to the factory to print the photos after taking 100 and reset them. Come 1949, the first disposable camera was made and distributed by Photo-pac. But it could not really be called popular since it could only take 8 pictures before you need to buy another. Jacques-Yves Cousteau invented the first waterproof camera, but it was big, bulky, and probably not meant for the general public. It was mostly used for military purposes. As you can see, there were many firsts in the long history of the camera. I learned quite a bit while writing this. I hope that you learned something reading it too.