Before computers, my father was a photographer and he developed his own photographs in a dark room. He used the Time-O-Lite to time the exposure of a negative onto photo sensitive paper. The image wouldn’t be visible until the paper was bathed in developer chemicals. It was magical.
I was of course, not allowed to play with the instruments in the dark room. So I was very careful when I did.
On the side are outlets for a safelight (usually red) and an enlarger (used to expose the negative to the photo sensitive paper). You could control the enlarger and the safelight with the timer for precision.
It is amazing that this complex analog process was completely replaced by digital photography. My father embraced the change. He bought a digital camera and I showed him how to use photoshop. He never looked back.
I listed this on facebook marketplace at $20 for about a month and then added it to a box of stuff I was taking to the municipal Eco-centre. Not an hour after I returned home I received an inquiry from someone who was ready to pick it up immediately. They were so disappointed. Even scolding, telling me “darkrooms are still a thing, you know!” I described the exact bin I’d put it in and they said they would go the next day to see if it was salvageable.