<P> Prints are created by transferring ink from a matrix or through a prepared screen to a sheet of paper or other material . Common types of matrices include: metal plates, usually copper or zinc, or polymer plates for engraving or etching; stone, aluminum, or polymer for lithography; blocks of wood for woodcuts and wood engravings; and linoleum for linocuts . Screens made of silk or synthetic fabrics are used for the screenprinting process . Other types of matrix substrates and related processes are discussed below . </P> <P> Multiple impressions printed from the same matrix form an edition . Since the late 19th century, artists have generally signed individual impressions from an edition and often number the impressions to form a limited edition; the matrix is then destroyed so that no more prints can be produced . Prints may also be printed in book form, such as illustrated books or artist's books . </P> <Table> External video <Tr> <Td_colspan="2"> Printmaking: Woodcuts and Engravings, Smarthistory </Td> </Tr> </Table> <Tr> <Td_colspan="2"> Printmaking: Woodcuts and Engravings, Smarthistory </Td> </Tr>

One of the reasons for the importance of printmaking is that