In intaglio printing, lines or tones are engraved or etched into the surface of a metal plate. The plate is inked and then wiped, leaving the grooves filled with ink and the surface clean. Soft, dampened paper is laid over the plate, and both paper and plate are put through the rollers of an etching press. The pressure of the rollers forces the paper into the grooves, so that it takes up the ink, leaving an indented impression of the whole plate on the paper. This impression is known as the plate mark. The two main kinds of intaglio are engraving and etching.
The question (& answer)
were taken from p. 238 of the New Artist’s Handbook by Ray Smith. The book was published by
Dorling Kindersley in 2003.