U.S. Post Office is a federal government agency responsible for mail delivery in the United States. It renders services pertaining to post and mails, catering to homes as well as businesses. The agency serves a variety of services, such as buying of stamps, pay print postage order, getting shipping supplies, change of address, putting mail on hold, postage calculation and delivery confirmation. The postal store provides products, including stamps, books, envelopes, historical event stamps, commemorative panels and press sheets, to name a few. U.S. Post Office also offers an array of shipping services, which include express mail, priority mail, first-class mail and international shipping.