RFID technology is an automated system of wireless data capture, consisting of two parts: the tag and the reader. The tag is a silicon chip that contains information transmitted to the RFID reader through radio waves. RFID tags can be embedded in products, government-issued ID cards, credit cards, toll devices and even people. Depending on the radio frequency and power source, readers can pick up the radio waves and read the stored digital information contained on the chip. RFID tags can contain personal information (e.g. a person's social security number, financial information, etc.) which, if not adequately protected, can be stolen by someone with a compatible reader within range of the RFID tags. Hence, RFID tags have the potential to put a person's safety, financial security, and privacy at risk.
Mariko Yoshihara, "RFID and Privacy" (Public Law Research Institute, Fall 2006) summarizes existing use of RFID technology, related privacy concerns, and discusses best practices for RFID regulation.