A tracking number is a unique identifier assigned to a package or shipment by a shipping company. It allows both the sender and recipient to monitor the package's journey from the point of origin to its final destination. This number can be used on the shipping company's website or app to check the current status and location of the package. When a package is shipped, the shipping carrier generates the tracking number, which is often included in the shipping confirmation email. This number can also be found on the shipping label attached to the package, making it easy to reference throughout the delivery process.