PDF417 (Portable Data File, also ISO 15438) is a stacked linear (hence two dimensional) barcode offering increased data density. A single PDF417 label store up to 1800 ASCII characters or 1100 binary characters per symbol. This is enough to store biometric data like photographs, fingerprints, and signatures, along with numbers, text and graphics. The label shape can vary to some extent by setting the width and allowing the height to grow with the data. This symbology was invented in 1991.
PDF417 allows to link multiple symbols (labels), storing even more data without the obvious upper limit. Also, public domain licensing may result lower costs of usage. PDF417 requires the 2D-capable scanner.
Along with the Data Matrix format, this PDF417 can be used to generate postage, acceptable by the United States Postal Service. PDF417 is also selected by the airline industry (Bar Coded Boarding Pass standard) and by the Department of Homeland Security (RealID compliant driver licenses and state issued identification cards).