Letterpress printing is an example of relief printing, the process in which printing ink is transferred to a printed surface from areas that are higher than the rest of the printing block. In the case of letterpress printing, each page of type is used as the mold for a papier-mache mat, which is actually a copy in reverse of that page of type. The mold in turn is used to make a metal copy of the entire page, and this metal copy is used for printing. This was the traditional way to print newspapers. Variations of this printing technique may use plastic or rubber plates. Because several plates can be made from each original, brand new type can be introduced at regular intervals, ensuring that copies remain sharp and clear.
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