The colony of Massachusetts established the first post office within the United State in 1639 , In 1789 Congress authorized the postal service under the U.S. Constitution. At the time, the nation had 75 local offices and delivered mail over an area of 1875 ml.
Today, the postal service is an independent agency responsible for regulation and delivery, The Postal Service main responsibilities are the collection and delivery of printed material and hard goods. The Postal Service also issues domestic and foreign money orders. In a single year, Postal Service handles more than 160 billion pieces of mail.