Final answer:
Bar codes on products help retailers build a profile about customer preferences by collecting transaction data over time, which is analyzed to understand and cater to buying patterns and trends.
Step-by-step explanation:
Bar codes on products purchased help retailers build a profile about customer preferences. When a product with a bar code is scanned at the checkout, the information is typically recorded in a retailer's point-of-sale (POS) system. Over time, this data accumulates and can be analyzed to understand buying patterns, preferences, and trends.
Through this analysis, retailers can create detailed customer profiles, tailor their marketing strategies, manage stock levels effectively, and potentially increase sales by targeting customers with more personalized offers based on their purchasing history.