tracking in usps allows you to monitor the progress of a package sent via USPS. By entering the tracking number provided by the sender, you can check the current location and estimated delivery date of your shipment. USPS offers tracking for many services, including Priority Mail, First-Class Mail, and Express Mail. You can track your package online through the USPS website, via mobile apps, or by using their customer service center. Tracking information is updated in real time to provide accurate delivery details.