International postal codes and encyclopedias are international postal codes used to distinguish different countries. There is no international postal code in China. If you send an international letter, you don't need a zip code. If you reply from abroad, a zip code is unnecessary. Postal code is computer sorting mail, and national mail is manual sorting. So zip code is not necessary.

Postal code is a scheme to realize automatic sorting of letters, because computers can't recognize Chinese, but they can recognize numbers. By coding each area, you can quickly sort it by computer. Of course, the finer you write, the better. The writing format of the cover of international mail shall be handled in accordance with the provisions of the Universal Postal Union.

Postal code:

Postal code is a special code composed of Arabic numerals, which represents the post office where mail is delivered, and it is also the communication code between residents and units within the delivery range of this bureau.

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 letters in the process of delivery. Therefore, it is necessary to specify the postal code when handing in letters and parcels. In order to realize the automation of mail sorting and the digitalization of postal network and speed up mail delivery.

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