The pinyin of stamp is yóu piào.

Postage stamps are postage certificates used to affix mail for delivery, and are generally issued by sovereign states. The square inches of stamps often reflect a country or region's history, science and technology, economy, culture, customs, natural features and other characteristics, which makes the stamps in addition to postal value in addition to the value of collection.

The birth of stamps was due to the change of the object of postage levy: reduced postage; billed by weight; pay postage first. Communication thus came into common use. Stamps are a form of payment by the sender for the postal service.

The three main elements of a postage stamp are:

Memorial: a mark printed on a stamp indicating the issuing country, region, or issuing organization, and expressed in words, abbreviated letters, or special marks. The stamp motto is one of the most important elements of a stamp, which can determine the issuing unit of a stamp.

Denomination: the amount of postage printed on the stamps and monetary units to indicate the amount of postage paid by the mail user. Most countries in the world use Arabic numerals and national currency units to form the face value of a stamp.

Pattern: The stamp pattern, which is the face of the stamp, is generally composed of three parts: the main picture, the text, and the border, which are related to the purpose of issuing the stamp. The content of the stamp design is all-encompassing, and people can gain a wealth of encyclopedic knowledge through the appreciation and study of the stamp design.