Radio-frequency identification 射频识别
（重定向自Radio id）
![Small RFID chips, here compared to a grain of rice, are incorporated in consumer products, and implanted in pets, for identification purposes](/Images/godic/202502/05/Microchip_rfid_rice4700.jpg")
![](/Images/godic/202502/05/FasTrak_transponder4700.jpg"){kind=spacer}
![Electronic Lock with RFID Card System, ANSI](/Images/godic/202502/05/Waferlock_Electronic_lock_WEL_3000A4700.jpg")
![Electronic key for RFID based lock system](/Images/godic/202502/05/RFkey4700.jpg")
Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify and track tags attached to objects. The tags contain electronically stored information. Passive tags collect energy from a nearby RFID reader's interrogating radio waves. Active tags have a local power source such as a battery and may operate at hundreds of meters from the RFID reader. Unlike a barcode, the tag need not be within the line of sight of the reader, so it may be embedded in the tracked object. RFID is one method for Automatic Identification and Data Capture (AIDC).