Framed diagram showing the principle of the Linotype

The Linotype printing machine was a linecasting machine developed by Ottmar Mergenthaler, a German-American inventor, in 1886. The Linotype was a hot metal typesetting system and the first printing machine that could easily and quickly set complete lines of type for use in printing presses.

This machine revolutionized the art of printing and society. Linotype printing machines were the dominant form of printers for newspapers and magazines from their invention to the late 1900s, when they were largely replaced by photosetting machines and soon afterwards electronic software.

Linotype machines were initially sold by the Mergenthaler Linotype Company, established by Mergenthaler in 1886. A British offshoot company, the Linotype Company, was established in 1889, becoming Linotype & Machinery Ltd in 1903.