Radio frequency identification: method of identifying items using radio waves. RFID is a wireless technology used to transmit information from tags attached to objects in order to automatically identify and track those objects.  RFID is a method to automatically collect data.  Radio frequency identification is often abbreviated using the term "RFID".

Typical characteristics of RFID technology...

A reader communicates with a tag, which holds digital information on a microchip (most, but not all, RFID technology uses a semiconductor-based microchip).  

RFID typically has low data transmission rates (but not always).

Most RFID technology has short transmission ranges (versus other wireless technologies like Bluetooth, ZigBee, WiFi and cellular).