Offset printing refers to a printing method where the inked image is "offset" (transferred) from a metal plate onto a rubber blanket and then to the printing surface. Offset printing is used primarily for large printing tasks. There are a number of offset printing machines available on the market.
Web Offset Machines
Web offset printing machines feed continuous rolls of paper through the printing press. After the pages are printed, they are separated and cut. This type of offset printing machine is used for printing high-volume publications, such as national or regional newspapers, magazines and mass-market books.
Sheet-Fed Offset Machines
As opposed to web offset printing machines, sheet-fed offset machines do not feed rolls of paper through the printing press, but instead feed only precut pages. Sheet-fed machines are not as economical for high-volume printing as web offset machines. However, they are easier to operate and maintain. In addition, they also often allow printing on cardstock, plastics and metal.
Quick Set Offset
Quick set offset machines are used for printing of high-quality images, such as trademarks, instruction books and some periodicals. Printing machines of this type are quick to set and dry slowly, allowing the printing machine to save ink. Furthermore, the printed materials dry faster than those printed on other types of offset printers.