Considered as "dots per square inch," a measure of output resolution in relationship to printers, imagesetters and monitors.<br><br>Dots per inch. A measurement of the scanning resolution of an image or the quality of an output device. Expresses the number of dots a printer can print per inch, or monitor can display, both horizontally and vertically. A 600-dpi printer can print 360,000 (600 x 600) dots on one square inch of paper.Related link: "The Illustrated Book Study" is a collaborative effort undertaken by Cornell University Library's Department of Preservation and Conservation and Picture Elements, Inc, and the Library of Congress. On its Illustrated Book Study Resolution Samples pages, visitors can examine digital images of prints of several types ? collotype, copper engraving, etching, halftone, lithograph, mezzotint, photogravure, steel engraving, and wood engraving ? at each of several resolutions ? dots per inch (DPI). Also see aspect ratio, moir?, and monitor.