"He who marches out of step hears another drum." ~ Ken Kesey
Funny that you show that, I was cleaning out some cabinets a few months back and found one of those machines and I didn't have a clue of what it was..we bought a bunch of stuff in a sell and it was in there.
I last used one of these in the late '70's.The silver thing houses the exposure light, and there were controls to advance or reverse the font film roll to the desired letter, then zap, expose, and move on.Then like Robert explained, developed the paper, cut, and paste, then shoot for film, then, make a screen.Getting my timeline down, this was in a flat stock screen shop in the mid '70's. around 1978, changed to an embossing and engraving shop running a die stamping press. That lasted until about '86, when I spent some time with family in Los Angeles, and re-honed my skills on small offset presses in a friend of my dad's shop.I remember he had a typesetting service that was pretty much using what we use now. Computers weren't an everyday thing in every shop yet.For further perspective on type and the times, in "real" print shops, and newspapers, during this same time in the '70's, my wife was running a Ludlow type- casting machine.