Robert Moon (postal inspector)

Robert Aurand Moon (April 15, 1917, Williamsport, Pennsylvania, USA – April 11, 2001, Leesburg, Florida, USA), sometimes called "Mr. ZIP", is considered the father of the ZIP Code or Zone Improvement Plan, a mechanism to route mail in the United States. He developed the idea in the 1940s while working as a postal inspector in Philadelphia, although his system used only the first three digits of what became a five-digit, and later a nine-digit, system. The first Directory of Post Offices using five-digit ZIP code numbers was published in 1963.