Lithograph

Invented at the end of the eighteenth century, a lithograph is a print produced by a method of surface printing. A design is drawn or painted on to a flat surface with a greasy ink or chalk and then water is washed over it. Oil-based printing ink is rolled on to the stone; it sticks only to the greasy parts, being repelled from the water-covered areas. Reverse prints are then taken on paper in a lithographic press. Popular for posters because it allows multiple production.