Barcode from ISBN
A barcode can be created directly from an ISBN, creating an ISBN barcode. The 13 digits of the ISBN become the 13 digits of the EAN13 barcode number.
ISBN barcodes can also have an additional (optional) 5 digit supplementary barcode after the main barcode. This is an optional extra barcode which can be sued to encode the book price in some countries. The first of the 5 digits indicates the currency – 0 & 1 = GBP, 3 = $AUD, 4 = $NZD, 5 = $USD, 6 = $CAN