The USPS has several classes of mail that mail services uses to process outgoing mail ... Contact mail services for additional information. Use Certified Mail to have access to information on delivery ...

USPS will not raise the prices on its "Market Dominant" products, which include certified mail; first-class mail; library ...

Certified mail service is available only for first class mail ... Express mail is a fast service available from the USPS. It reaches all major markets in the U.S. and 84 foreign countries. Express ...