All goods for sale in supermarkets have bar codes
which contain data that can uniquely identify the
items.
The bar code is read by a bar code
scanner/reader at the checkout and the
data is read and used to look up the item
in a database on the supermarket's
computer system.
Self-service checkouts work
because all the information about
the item does not need to be
entered again since it is already
on the store database.
The customer scans the bar code
and the details are retrieved and
displayed on the screen.
scan the items on the shelves
count the number of items on the shelf
count the number of items on the shelf
send thr data to thr store computer
system to update the database so the
store knows how many items are in
sock.
Radio Frequency Identification (RFID)
Tag are small devices which use radio waves to transfer data from the tag to a computer system.
RFID tags are used by supermarkets to automatically identify items.
Near field communications (NFC) are used in smartphones to create radio links p0ver a very short range of a few centimetres or less.
A smartphone using NFC is touched or waved very close to another device to: exchange data such as a configuration for Wi-Fi
Make contactless financial transactions, e.g. pay for parking
Fast data transfer of transaction details similar to those in credit cards
NFC sets itself to faster then Bluebooth and there is no need for
pairing but, data transfer is slower then Bluebooth.