An RFID primer

RFID tags would replace the bar code - the little 28-digit strip of stock-keeping unit numbers read by laser scanners. Smaller than a pinhead and thinner than a greeting card, the more sophisticated 128-bit computer chips come attached to a small antenna. Glued to a product, the transmitter broadcasts a signal that identifies each item plus its color, size, maker and date of manufacture. That means its path can be traced in real time from manufacturer to truck, warehouse and store down to the exact shelf until a customer takes it out the door.