ZIP codes were introduced in the early 1960s, as a tool to improve the efficiency of mail delivery by the United States Postal Service. The acronym ZIP stands for Zone Improvement Plan, and, in 1963, the USPS introduced non-mandatory ZIP codes across the country. Typically, a ZIP code is five digits long, but it can sometimes include a hyphen followed by four digits to specify a more specific area. This is known as an expanded ZIP code and was introduced in 1983 to designate a very specific area, such as an a block of houses or a company that receives a very high volume of mail.
Initially, ZIP codes were only used to improve mail delivery speed by the USPS, but, as of 2015, ZIP codes are used by private mail carriers to improve mailing speed and many marketing companies use customers' ZIP codes to help create accurate marketing campaigns and refine promotions. ZIP codes are also used by business websites to offer customers pertinent information, such as regional promotions or the nearest business locations.Learn more about Postal Services