The principles of photography really haven’t changed all that much since its early beginnings. The technology has come a long way, the recording mediums have evolved, but the fundamental principles are still the same. You still need a light tight box (your camera body), something to project light from your scene to the inside of the box (a lens), something on which to record it (film or a sensor) and a way to control the exposure (shutter).
In this 1948 training film from the US Navy, we learn about the history of photography as it stood at that time. We take a look at the original camera obscura and how it evolved into the bleeding edge technology of mid 20th century. That technology may be a far cry from where it is today, but some things never change.