USPS is an acronym for the United States Postal Service. Other names include the Post Office, U.S. Mail or the Postal Service. The USPS is an independent agency that is held responsible for delivering postal service.
The original name for the USPS was the U.S. Post Office Department. It was originally run by the U.S. government. After 1971, it became an independent agency separate from the government.
Any piece of mail or parcel that is to be delivered by the USPS is required to have specific information. This includes legible complete delivery address and return address. All pieces of mail must also have the right amount of postage to get delivered.