What is a Scanner?

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A Scanner is an optical input device that uses light-sensing equipment to capture an image on paper or some other object. The image is translated into a digital signal that can be manipulated by optical character recognition (OCR) software or graphics software. Scanners come in a number of types: Flatbed Scanner:: A scanner that provides a flat, glass surface to hold pages of paper, books and other objects for scanning is a flatbed scanner. The scan head is moved under the glass across the page. Sheet feeders are usually optionally available that allow multiple sheets to be fed automatically. Handheld Scanner: A handheld scanner can be moved across the image to be scanned by hand. Hand-held scanners are small and less expensive than their desktop counterparts, but rely on the dexterity of the user to move the unit across the paper. Trays are available that keep the scanner moving in a straight line.

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