Cheap, tiny, plentiful radio-frequency identification tags can make it possible to tag almost everything, spurring a revolution in how physical objects interact with information services. It uses radio waves to read an object's markings in the form of a unique identifying number stored on an attached or embedded silicon chip. Unlike active tags, passive tags provide only an identifying number, when the tags themselves are 'illuminated' by the radio waves emitted by a specialized reader. The sampling of RFID technologies and their applications will help show its possibility in consumer uses of passive RFID tags.