1. It can be divided into six categories according to the scope of use:

1. Domestic postage paid date stamp. It is a postal date stamp indicating that domestic postage has been paid. It can only be stamped on domestic single-pay and single-pay mail items of more than 10 pieces. Before 1993, there was an all-Chinese character style; from June 30, 1993, it was changed to Chinese and French; from August 1995, it was changed to a new postage-paid date stamp without ruled lines in the box. In the autonomous region, minority languages ??are used together with Chinese.

2. International postage is stamped and paid. Postal date stamp used for payment of bulk international mail charges. Officially launched in 1962, there are four types: full foreign language, engraved postal code (from 1985), Chinese and French (from June 1993), and new postage paid date stamps.

3. Postage for Hong Kong and Macao has been stamped. Postal date stamp specially used for payment of bulk mail charges in Hong Kong and Macao. Its characteristic is that the Chinese characters "Hong Kong and Macao postage paid" are engraved in the upper box. In 1985, postal codes were added, and from June 1993, postage-paid date stamps in Chinese and French were used.

4. Taiwan postage has been stamped and paid. Postal date stamp specifically used for payment of bulk mail charges to Taiwan. Used in provinces and cities that send a lot of mail to Taiwan. There are two types: full Chinese and engraved postal code. From June 1993 onwards, Chinese and French postage-paid date stamps were used.

5. Confidential postage has been stamped. Postal date stamp dedicated to the payment of fees for sending confidential mail. The stamp is engraved with "Confidential Correspondence Postage Paid" to indicate the difference.

6. The express postage has been stamped and paid. The postal date stamp indicating the payment of express mail charges. It has been gradually used since 1980. The postmark usually has "Express Mail Postage Paid", "(Express Mail)", "Express Delivery", "EMS" (English abbreviation of Express Mail), "DEM" (English abbreviation of Domestic Express Mail). ) and other words to indicate the difference.

2. According to the stamping method, it can be divided into two types: hand stamped with postage paid and date stamped with machine stamped with postage paid. The hand stamps are all made with black ink, and the machine stamps are all red ink. There are two types of cover stamps: single stamp and combined stamp. In addition to the octagonal single stamp, the author also has a square stamp, which is used by Shanghai 82 (branch). Combination stamps can also be combined with promotional stamps, corrugated stamps, and double-round date stamps.

3. According to the usage function, there are two types: general postage-paid date stamps and special postage-paid date stamps. The Chinese-French postage-paid date stamps that have been used since June 30, 1993, and the new postage-paid date stamps that have been used since August 1995, are all international and domestic postage-paid postmarks, except those marked for special use. In addition to the special postage-paid date stamps for international, Hong Kong, Macao, Taiwan, confidential, and express mail, there are also special postage stamps within the post office, such as "printing", "hanging brush", "cover brush", "flat brush", "Sorting", "Business", etc. are all engraved with Chinese characters on the postage-paid date stamp surface to show the difference.

4. According to the place of use, it can be divided into three categories: post office, post and telecommunications branch office, and post and telecommunications. The ones used by the post office can be subdivided into three branches: provincial (municipal) bureau, municipal bureau, and county bureau, and the ones used are all engraved on the postmark.

5. According to the characters engraved on the stamp surface, they can be divided into all Chinese, all foreign languages, Chinese, French, Chinese, French and Chinese pinyin letters, Chinese and minority languages.

6. According to the stamp surface style, it can be divided into five types: three-square unequal spacing, three-square equidistant, zigzag, national standard (GB standard) and new style unformatted.

7. According to the stamp material, it can be divided into two types: steel postage-paid date stamps (5, 6, etc.) and gelatin postage-paid date stamps (ie, ink storage type postage-paid date stamps). In addition to the common pin type, the new postage-paid date stamp also adds a dial type. The difference is the century and year number. The pin type is still 4 digits, while the dial type is changed to 2 digits, month and day. If it is a single digit, it can be represented by a leading "0" to become a 2-digit number.

8. According to the standards issued by the ministry, it can be divided into two types: standardized postage-paid date stamps and non-standard postage-paid date stamps.