Radio frequency identification, or RFID, is a term for technologies that use radio waves to automatically identify objects. The most common method of identification is to store a serial number that uniquely identifies the object. This serial number is globally unique number and stores important information like product manufacturer information, product type, and unique product identification ID. The RFID system includes a RFID transponder/tag and a reader. RFID tag compromises of a chip and an antenna. The antenna enables the chip to transmit the unique identification information to the reader. The reader converts the radio waves from the RFID tag into digital information that can then be passed on to computer applications to process the information.
RFID uses wireless technology operating with the 50 KHz to 2.5 Ghz frequency range. RFID does not require line-of-sight to operate for communications between a tagged object (which could be almost anything including a car, merchandise, package, etc.) and a reader (an electronic device used to capture the RFID signal).

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