A barcode is a row of thick and thin vertical bars, often with 14 numbers, that can be read by a computer.
Barcodes appear on most supermarket products, on books, on library cards and many other items.
Barcodes are read by a 'barcode reader' which detects the patterns of light and dark and transmits the data to a computer.
One of the key advantages of a barcode system is that it does *not* contain price information. Prices change all the time, often every day as bargains come and go. What the barcode provides is the *location* of the record for that item within the stock database. So if a price changes, only the database record need change.
Challenge see if you can find out one extra fact on this topic that we haven't already told you
Click on this link: Barcode