Near Field Communication
Near field communication is a set of standards for smartphones and similar devices to establish radio communication with each other by touching them together or bringing them into close proximity over about a 10 cm distance. NFC is an upgrade of the existing proximity card standard (RFID) that combines the interface of a smartcard and a reader into a single device. Allows users to seamlessly share content between digital devices, pay bills wirelessly or even use their cell phone as an electronic traveling ticket on existing contactless infrastructure. 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 . Due to its shorter range, NFC provides a higher degree of security than Bluetooth and makes NFC suitable for crowded areas where correlating a signal with its transmitting physical device (and by extension, its user) might otherwise prove impossible. NFC can also work when one of the devices is not powered by a battery.
Source
http://en.wikipedia.org/wiki/Near_field_communication
http://www.gsmarena.com/glossary.php3?term=nfc
http://developer.android.com/guide/topics/connectivity/nfc/index.html