Cultural and historical differences have created differences in the way mail is addressed. As the processing of mail within countries has become more centralized, these differences became the basis for the rules created by the various postal authorities around the world. (These systems and formats do not remain fixed. In just the last ten years, more than 100 changes in postal formats have occurred.)
Countries have, and retain, their own culturally accepted methods of addressing mail. Some countries have short, two- or three-line addresses. For some, the elements of an address are longer, with six or seven lines a necessity for all the address information to be included. Descriptive addresses (“in the basement next to the supermarket” or “across the street from the movie theatre”) have proved to be very resistant to change when countries introduce more formal addressing systems.
Some variations do go out of use. The “inverted” format with the name of the country at the top of the address and the recipient at the bottom, common in the U.S.S.R. and some eastern European countries, has fallen out of use. (It is still seen in domestic mail in some countries there.) However, the differences between these countries have remained as the order of the lines changed but not the address elements.
Changes to addresses occur as countries modify address formats and institute postal codes to make mail processing more efficient. As this occurs, the traditional address format for a country is often standardized and simplified. Although, these specifications can create changes in common cultural practices for individual correspondence, they also institutionalize them.
Recently some countries have created new national addressing systems or significantly expanded their addressing systems. In most cases, these new systems share some elements, such as postal codes. But the most interesting aspect of these new address systems is that each is unique, different from each other and from those of other countries.