Optical scanner is a device that can read text or illustrations printed on paper and translate the information into a form the computer can use. A scanner works by digitizing an image.
Some scanners are small hand-held devices that you move across the paper. These hand held scanners are often calledhalf-page scanners because they can only scan 2 to 5 inches at a time. Hand-held scanners are good for scanning small pictures and photos, but they are difficult to use if you need to scan a large page.
Larger scanners include machines into which you can feed sheets of paper. These are calledsheet-fed scanners. Sheet-fed scanners are excellent for loose sheets of paper, but they are unable to handle bound documents.