RFID is called Radio Frequency Identification. This is a technology where radio waves are used for tracking an item. For example, it is possible to track a library book with this technology. By using radio frequency identification, objects or individual can be repeatedly detected. Different methods for identification are there but the most common is to get a serial number.
This can be kept on a microchip that is connected with an antenna and discover an object, a person or other information. You may search for the RFID Chip Timing Reading Pennsylvania on the Internet to get useful information on this regard.