Near Field Communication

Near Field Communication or NFC, is a short-range high frequency wireless communication technology which enables the exchange of data between devices over about a 10 centimeter (~4 inches) distance. The technology is a simple extension of the ISO 14443 proximity-card standard (contactless card, RFID) that combines the interface of a smartcard and a reader into a single device. An NFC device can communicate with both existing ISO 14443 smartcards and readers, as well as with other NFC devices, and is thereby compatible with existing contactless infrastructure already in use for public transportation and payment. NFC is primarily aimed at usage in mobile phones.

Uses and applications
NFC technology is currently mainly aimed at being used with mobile phones. There are three main use cases for NFC:

- card emulation: the NFC device behaves like an existing contactless card
- reader mode: the NFC device is active and read a passive RFID tag, for example for interactive advertising
- P2P mode: two NFC devices are communicating together and exchanging information.

NFC vs. Bluetooth
NFC and Bluetooth are both short-range communication technologies which have recently been integrated into mobile phones. The significant advantage of NFC over Bluetooth is the shorter set-up time. Instead of performing manual configurations to identify Bluetooth devices, the connection between two NFC devices is established at once (<0.1s).>

Source : http://en.wikipedia.org/wiki/Near_Field_Communication