Linotype machine

The linotype machine (/ˈlaɪnətaɪp/ LYN-ə-typ) is a "line casting" machine used in printing sold by the Mergenthaler Linotype Company and related companies. It was a hot metal typesetting system that cast blocks of metal type for individual uses. Linotype became one of the mainstay methods to set type, especially small-size body text, for newspapers, magazines and posters from the late 19th century to the 1970s and 1980s, when it was largely replaced by phototypesetting, offset lithography printing and computer typesetting. The name of the machine comes from the fact that it produces an entire line of metal type at once, hence a line-o'-type, a significant improvement over the previous industry standard, i.e., manual, letter-by-letter typesetting using a composing stick and drawers of letters.

The linotype machine operator enters text on a 90-character keyboard. The machine assembles matrices, which are molds for the letter forms, in a line. The assembled line is then cast as a single piece, called a slug, of type metal in a process known as hot metal typesetting. The matrices are then returned to the type magazine from which they came, to be reused later. This allows much faster typesetting and composition than original hand composition in which operators place down one pre-cast glyphs (metal letter, punctuation mark or space) at a time.

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