A serial number is a unique identifier assigned to an individual item, product, or component. It helps distinguish one item from another, even if they are part of the same batch or model. Manufacturers use serial numbers for tracking, warranty claims, and quality control. Typically, a serial number can be found on the product itself, often on a label or engraved on the item. It may consist of letters, numbers, or a combination of both. For example, electronics like smartphones and laptops often have serial numbers to assist in customer support and service.