Printmaking is the process of creating artworks by printing, normally on paper. Printmaking normally covers only the process of creating prints that have an element of originality, rather than just being a photographic reproduction of a painting. Except in the case of monotyping, the process is capable of producing multiples of the same piece, which is called a print. Each print produced is considered an "original" work of art, and is correctly referred to as an "impression", not a "copy". Often impressions vary considerably, whether intentionally or not. The images on most prints are created for that purpose, perhaps with a preparatory study such as a drawing. A print that copies another work of art, especially a painting, is known as a "reproductive print".