Linotype 

The linotype machine is a "line casting" machine used in printing. Along with letterpress printing, linotype was the industry standard for newspapers, magazines and posters from the late 19th century to the 1970s and 1980s, when it was largely replaced by 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.

How does the Linotype work?

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 metal letter, punctuation mark  or space at a time.

The New York Tribune

 The New York Tribune first integrated the machine into its operations in July 1886. Before its invention and implementation, no newspaper could easily run longer than a few brief pages, and this new way of producing text marked a radical evolution in the history of printing and typography.

How did it change Printing?

The machine revolutionized typesetting and with it especially newspaper publishing, making it possible for a relatively small number of operators to set type for many pages on a daily basis. Before Mergenthaler's invention of the linotype in 1884, daily newspapers  were limited to eight pages.

Keyboard



The keyboard has 90 keys. There is no shift key; uppercase letters have keys separate from the lowercase letters. The arrangement of letters corresponds roughly to letter frequency, with the most frequently used letters on the left.
The first two columns of keys are: e, t, a, o, i, n; and s, h, r, d, l, u. A Linotype operator would often deal with a typing error by running the fingers down these two rows, thus filling out the line with the nonsense words etaoin shrdlu. This is known as a "run down". It is often quicker to cast a bad slug than to hand-correct the line within the assembler. The slug with the run down is removed once it has been cast, or by the proofreader.

See Some Examples
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