Aquatint is a variation of etching; it is an intaglio technique used in printmaking. In this kind of printmaking, a person creates impressions on a matrix (a zinc/copper plate in regards to aquatint) containing ink. After this step, the plate and a paper sheet are inserted in a printing press. The end product is paper coated with an ink layer; this step can be repeated as desired by the artist. Acid is used in aquatint in order to create the impressions on the metal plate. This is different than the engraving method in which a person uses a needle to create the impressions. Aquatint employs rosin in order to make the value gradations. Rosin holds onto the plates surface by heat and resists acid. An image is formed one part at a time by the artist maneuvering the degree of acid exposure over the piece's areas to control the tonal variations. The famous artist Goya (1746 - 1828) created images completed in aquatint with drypoint and/or etched lines. At present, the method of aquatint is favored for use by graphic artists, and is particularly favored when it comes to completing prints in color.