When headlines were set using a machine that used a photo process, which I think started in the mid fifties, type kerning became a real possibilty, as did special effects.
Body type, when still set in lead, made do with combinations of characters called ligatures instead of kerning. Ligatures where combinations of letters like t and h, or f and l, and the like. Photo typesetting, using negative images of type stored on glass or film or trasnmitted by CRTs, made kerning possible on text.
When computers began to take over the typesetting business in the early 70s, kerning became widespread before moving to PCs (and by that I mean the Macintosh) in the 80s.
Thanks much. Very interesting. From time to time it must even have helped squeeze a headline into the alloted space.