RFID in Retail
RFID is probably a lot older, and used more widely, than most people realize. It has been used to tag cattle on ranches so they can be tracked and identified for years. It is what veterinarians use when they tag pets. Other common uses include electronic access control keys, and heavy duty versions for tracking shipping containers, machinery, railroad cars and so on.
The technology is also widely used in retail, as the anti-theft detection tags which are linked to store alarm systems. However, this is a very basic use of RFID.
Because they are basically a microchip with an antenna, RFID tags are capable of storing huge amounts of information about a product - date of manufacture, date of shipping, serial number, price, size, color and so on. With the right kind of radio scanner, this data can also be edited. So, for example, you could set up a system where the purchase date is added to the chip when it is scanned at point of sale.
This is why so many people believe RFID is still the future of POS, not so much for the possibilities of walk through checkouts, but for improving stock control and even supply chain logistics. Once an RFID tag is scanned at a POS terminal, the central computer immediately knows everything about that item. Stock data can be updated in real time, it can be replaced on the shelf more quickly, and if stocks are low it can even trigger an order to the supplier.