Postal code is a special code for postal communication to realize mail sorting, and it is a necessary tool to realize postal modernization. The ultimate goal is to improve the speed and accuracy of your letters in the delivery process, so be sure to indicate the postal code when handing in letters and parcels. If you don't know the postal code of the other party (the recipient), you can inquire on the postal code inquiry machine or postal multimedia microcomputer inquiry system set up in the local post office, or through the special telephone of1185. In order to realize the automation of mail sorting and the digitalization of postal network, and speed up the delivery of mail, more than 40 countries in the world have successively implemented postal coding system, which is regarded as one of the standards to measure the communication technology and postal service level of a country. Postal coding rules in different countries are not uniform. China postcode coding rules: China adopts a four-level six-digit coding system, with the first two representing provinces, municipalities and autonomous regions, the third representing postal areas, the fourth representing counties and cities, the last two representing delivery post offices, and the last two representing which delivery area of the city to deliver, that is, the location of the delivery area. For example, the postal code "13002 1"13 "represents Jilin Province," 00 "represents Changchun, the provincial capital, and" 21"represents the delivery area. Coding rules of U.S. postal code: Postal code is postal code, and U.S. postal code uses capital letters. Postal code is an acronym for regional improvement plan, but it is also cleverly thought to imply the fact that when the sender uses it, the mail spreads more efficiently (and therefore faster). The basic postal code consists of five digits. The extended ZIP+4 code includes five digits plus four digits of the postal code, allowing mail to be sent to a specific address. Zip code is a registered trademark of the United States Postal Service. Postal codes are numbered like this. The first number represents a small group of states in the United States, the second and third numbers together represent a region (or possibly a big city) in the group, and the fourth and fifth numbers represent more specific regions, such as small towns or regions in the city. Major towns in this area (if possible) usually get the first postal code in this area; After that, numerical commands often follow alphabetical order. Like area codes, postal codes are divided and sometimes change, especially when rural areas become suburbs. Coding rules of French postal code: French postal code starts from 1972 and uses * * 6 digits, with the first two digits representing provinces and the last three digits representing cities, regions or post offices respectively. Japan Postal Code Rules: The new postal code system developed by Japan Post was put into use on February 2nd, 1998. The purpose of developing the system is to meet the needs of the expanding postal mechanization operation, improve the operation efficiency and ensure to provide users with stable, cheap and high-quality services. Its main features are: the number of postal code digits is 7, and the character "-"is used between the first three digits and the last four digits; Text structure: At present, all numbers are used; The connection between the old and new postal code systems: three or five digits in the old code are taken as the first digit of the new code; The particularity of the new code: every small part of the address (such as CHO and OAZA) is designated as a number, which is connected after the existing postal code. Business centers such as large enterprises can have special coding problems: I still don't understand.