The United States Postal Service (USPS) is a government-run organization that provides MAIL delivery services to citizens of the United States. USPS Delivery is a service provided by the USPS that allows customers to send letters and packages to their desired destination. The term USPS Delivery can be broken down into two parts: MAIL (4 letters) and LTR (3 letters). MAIL refers to the physical items that are sent through the USPS, such as letters, postcards, and packages. LTR stands for Letter, which is a type of MAIL item that is sent through the USPS. USPS Delivery is a convenient and reliable way to send items to their intended recipient.