Phototypesetting

Phototypesetting was a method of setting type, rendered obsolete with the popularity of the personal computer and desktop publishing software, that uses a photographic process to generate columns of type on a scroll of photographic paper. Typesetters used a machine called a phototypesetter, which would quickly project light through a film negative image of an individual character in a font, through a lens that would magnify or reduce the size of the character onto photographic paper, which would collect on a spool in a light-tight canister. The photographic paper would then be fed into a processor, a machine that would pull the paper strip through two or three baths of chemicals, where it would emerge ready for paste up.

Read more about Phototypesetting:  History