Planographic printing means printing from a flat surface, as opposed to a raised surface (as with relief printing) or incised surface (as with intaglio printing). Lithography and offset lithography are planographic processes that rely on the property that water will not mix with oil. The image is created by applying a tusche (greasy substance) to a plate or stone. (The term lithography comes from litho, for stone, and –graph to draw.) Certain parts of the semi-absorbent surface being printed on can be made receptive to ink while others (the blank parts) reject it. (Wikipedia).
This group of prints reflects the one-of-a-kind quality of the monotype print process. (Image: http://www.gelatine-printing.eu/?start=32)
Monotyping is a type of planographic printmaking made by drawing or painting on a smooth, non-absorbent surface. Monotyping produces a unique print, or monotype; most of the ink is removed during the initial pressing. Although subsequent reprintings are sometimes possible, they differ greatly from the first print and are generally considered inferior. These prints from the original plate are called “ghost prints.” A print made by pressing a new print onto another surface, effectively making the print into a plate, is called a “cognate”. Stencils, watercolor, solvents, brushes, and other tools are often used to embellish a monotype print. Monotypes can be spontaneously executed and with no previous sketch.