Another input device that is being increasingly used is the scanner. Often, there are situations when some information (picture or text) is available on paper and is needed on the computer disk for further editing. The simplest way would be to take a photograph of the image directly from the source, and convert it into a form that can be saved on the disk and then printed.

Flat-bed Scanner

Flat-bed Scanner

A scanner scans an image and transforms the image to ASCII codes that is the code used by a computer to represent the characters you find on your keyboard—letters of the alphabet, numbers, punctuation marks and graphics. These can be edited, manipulated and printed.

Scanners are of two types—the flat-bed type and the roller-feed type. While in a roller-feed scanner, the image is passed over a roller where it is captured, the flat-bed scanner works like a photo-copier. Flat-bed scanners can scan and store images from books without having to remove the page, which is difficult in the case of the roller-feed scanner.

Many of the scanners available now-a-days are capable of not only scanning text and graphics, but also integrating text and graphics files.

Scanners are used to reproduce photographs on the computer screen. They can be employed in training programs using the computer and in desktop publishing. Businesses use scanners for storing documents on the computer.