Radio-frequency Identification (RFID) uses electronic tags that can identify and track individual items such as book, jugs of laundry detergent, automobiles, or even people. One of the best-known uses of RFID is OnStar, which is a satellite-based RFID system used in automobiles. RFID tags emit radio signals that can be read remotely by electronic readers and provide precise, real-time information about the location of specific items, whether it be a Cadillac with a deal battery, a misplaced book in a bookstore, or a pallet of merchandise in a warehouse. Although RFID is also used by manufacturing firms, the technology has revolutionized services. The biggest names in retail, including WalMart, Home Depot, Carrefour and Tesco, are taking advantage of the new technology. Dutch bookseller Selexyz tags every book on its shelves with RFID, which increases profits and cutcosts since there's no more taking inventory by hand, fewer lost books, and fewer returns to publishers. The potential of RFID for retailers is enormous, which has prompted many companies to require that suppliers use the new technology.