We come accross barcodes almost everywhere nowadays. Most commonly when we buy groceries in our next door supermarket. The nice lady at the cash registrar no longer has to type in every single tem we take out of our shopping cart, she just picks them up and drags them accross a barcode reader - a scanner.
Barcodes are extreemly well suited for product and quality surveillance. The product id can easily be combined with a production machine identifier and a production date and time(batch identifier), then placed directly on the produced item. At a later time whole batches can be quality checked or barred from delivery based on such information as producing machine or production time.
Barcodes are also very practical when it comes to inventorizing complete stocks and ware houses. Barcodes accelorate the retrieval and delivery of items from stock piles.