Barcode is the easiest way to encode the information on the card. Information is encoded in the form of dark lines of varying thickness. The information contained in the code read by a scanner.
The most common barcodes are::
In the artwork of plastic card there should be a white area for a barcode. Without the blank space the number can be difficult to read by scanner.
Minimum size of the white area for barcodes:
EAN-13, width 40mm, min. 32mm
EAN-8, width 28mm, min. 22mm
code 128, width 32mm, min., 25mm
code 39, width. 46mm, min. 36 mm
ITF 2of5, width min. 22mm
Nowadays the most popular is QR code (Quick Response code). It's very easy to scan by mobile device or other device equipped in simple software which is available in the Internet for free. QR codes are used almost everywhere.