Barcodes are a series of black and white lines that represent data in a way that machines can read. They are commonly found on products in stores, allowing cashiers to quickly scan items at checkout. Each barcode is unique to a specific product, helping to track inventory and sales efficiently. When a barcode is scanned, a barcode scanner interprets the pattern of lines and converts it into numbers or letters. This information can include the product's price, description, and even its manufacturer. Barcodes make shopping easier and help businesses manage their stock effectively.