photo.jpg

## Typical input devices Optical character recognition (OCR) readers - Optical character recognition (OCR) technology is software that scans documents containing texts and converts them into documents that can be easily edited, stored or searched. - This text can be typed or handwritten or taken fr...

## Typical input devices Optical character recognition (OCR) readers - Optical character recognition (OCR) technology is software that scans documents containing texts and converts them into documents that can be easily edited, stored or searched. - This text can be typed or handwritten or taken from a scanned document, image, graphic or even a photo. ### Figure 2.13 Post offices use OCR readers to sort letters. ### Figure 2.14 A barcode ### Barcode readers - A barcode is a set of vertical lines of differing thickness with a string of numbers printed at the bottom (see Figure 2.14). - When used in a supermarket information system, barcodes provide a lot of information. - When the cashier at the checkout counter passes an item over the scanner in the counter, a laser beam scans the item's barcode and the beam is reflected back from the barcode into the scanner. - The information provided by the differing line thicknesses in the barcode is then sent to a computer for processing. - The store's computer can tell from the information in the barcode that one unit of this particular item has just been sold. - This information helps the store manager decide when to order more stock of the item. - Using the item number detected in the barcode, the computer also searches its memory to find the matching item number. - The computer can then send information to the cashier's display screen, such as the price and name of the item. ### Figure 2.15 Libraries use barcode scanning to keep a record of all books borrowed and returned. - When the customer receives his or her receipt, the computer will have printed the name and price of the item on the receipt, as well as added up the total price of all the items bought. - The barcode reading system, therefore, is a fast and error-free data entry method into the store's computer. - This system also provides a quick method of recording the sale of items. - Barcodes are also used in other information systems such as libraries and warehouses.