Unlike Visa and Mastercard which only process but not issue credit cards, and like Discover, American Express also issues credit cards. The origin of American Express is also very distinguished from those of the competitors. They started out as a domestic express mail service back when the US Post Office did not yet deliver packages. They made a lot of money, and very quickly established the American Express brand as a premium service provider. Later on, American Express gradually transformed itself into a financial services company while skillfully retaining and enhancing the brand nationwide and worldwide.