A barcode scanner is a device that reads the information encoded in a barcode, which is a series of parallel lines or squares that represent data. These scanners use a light source, typically a laser or LED, to illuminate the barcode and capture the reflected light. The scanner then converts this light into digital data that can be processed by a computer or point-of-sale system. Barcode scanners are commonly used in retail, inventory management, and logistics to quickly and accurately track products. They help streamline operations by reducing manual data entry errors and speeding up the checkout process, making transactions more efficient for both businesses and customers.