Hot type is a retronym. When metal type was the only game in town, it was just called type, but as more and different means of transferring ink to paper came into being a qualifier needed to be retroactively added. Hot type. Type that was once molten. Type that was once hot.
Foundry type, linotype, monotype are all forms of type that have been cast from molten metal. They are little pieces of sculpture carefully cast according to the strictly monitored vision of an artist.
Eric Gill (who’s art probably sits, in a derivative form, on your computer right now) was a sculptor. He worked in multiple mediums. He worked in stone, on a large scale, and cut beautiful life-like pieces from inanimate rock. He also used the same sorts of reductive processes when he engraved sensuous images of passionate lovers into boxwood and maple. And those images he printed alongside his type.
His type, too, is sculpture. Cut to size from steel punches and then struck into brass matrixes, Gill’s letterforms were cast in the millions. Like the human figure, we know what a letter should look like, and we can recognize a lovely figure when we see it. Gill’s type forms have stood the tests of time and, even more than Michelangelo’s David, are visited daily by multitudes.
Eric Gill once said that “letters are things not pictures of things” and, like his other sculptures, his letter forms are things. They are beautiful things. They are sexy things.
In their original form, they are hot.
So perhaps hot type is not such a retronym after all.