Sheetfed presses are printing machines used to print on individual sheets of paper, cardboard or other flat materials. Unlike web presses, sheet-fed presses are used when printing shorter runs or materials with different sizes. Sheet-fed presses are usually offset presses that can use a variety of colors to print a high-quality image or graphic on the surface of the material. Sheets are usually fed and aligned automatically to ensure accurate printing. Most modern sheet-fed presses are computer-controlled and can operate very quickly, often printing several thousand sheets per hour. Sheetfed presses are often used for the production of magazines, books, brochures, catalogs, flyers and other printed products.