RFID or radio frequency identification has been there since 2nd world war. Actually the technology is there since 1920. RFID tags include an antenna and silicon chips for sending the data to the wireless reader. Thus, the tags are not needed to be kept near the scanner for reading the data of the RFID tags.
The wireless reading device can read several tags within a second. This technology becomes also popular among the pet owners. You may search for the RFID chip timing Charleston South Carolina on the Internet to get useful information on this regard.