Personal identification numbers have different names and formats in different countries. Since you asked in Chinese, the following content mainly uses China's **Resident Identity Card Number** (referred to as ID card number) as an example. If you need information about personal identification numbers in other countries, please let me know. ### Overview of China's Resident Identity Card Number China's Resident Identity Card Number consists of 18 digits, and the specific structure is as follows: 1. **First 1-6 digits**: **Address Code** Indicates the ID card holder's registered place of residence, including province, city, district (county). For example, 110000 represents Beijing. 2. **7th-14th digits**: **Date of Birth Code** Indicates the holder's date of birth, in the format of YYYYMMDD. For example, 19900101 means born on January 1, 1990. 3. **15th-17th digits**: **Sequence Code** These three digits are used to distinguish different individuals with the same address code and date of birth code. Odd numbers are usually assigned to males and even numbers are assigned to females. 4. **18th digit**: **Verification code** Calculated from the first 17 digits through a specific algorithm, it is used to verify the validity of the ID number. The verification code can be a number from 0 to 9 or the letter X (representing 10). ### Detailed explanation of the generation method#### 1. Address code (first 6 digits) The address code is determined according to the national standard "National Standard of the People's Republic of China GB/T 2260-2007". Each province, city, district (county) has a unique six-digit code. For example: - Beijing: 110000 - Shanghai: 310000 - Shenzhen, Guangdong Province: 440300 #### 2. Date of birth code (7th-14th digits) The format is YYYYMMDD, indicating the holder's date of birth. For example: - January 1, 1990: 19900101 - December 31, 1985: 19851231 #### 3. Sequence Code (15th to 17th digits) The sequence code is used to distinguish different individuals with the same address code and date of birth code. Usually, odd numbers are assigned to males and even numbers are assigned to females. For example: - Males: 001, 003, 005, etc. - Females: 002, 004, 006, etc. #### 4. Check Digit (18th digit) The check digit is calculated from the first 17 digits by the following steps: 1. **Weight Factor**: Each digit has a corresponding weight factor, from the first to the 17th digits are: 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2. 2. **Calculate the sum**: Multiply the first 17 digits by the corresponding weight factor and then sum them. For example, the first 17 digits of an ID card are: 11010519491231002. The calculation method is: ``` (1×7) + (1×9) + (0×10) + (1×5) + (0×8) + (5×4) + (1×2) + (9×1) + (4×6) + (9×3) + (1×7) + (2×9) + (3×10) + (1×5) + (0×8) + (0×4) + (2×2) ``` 3. **Modulo operation**: Divide the sum by 11 and take the remainder. 4. **Determine the check code**: The check code corresponding to the remainder is as follows: | Remainder| Check code| |------|--------| | 0 | 1 | | 1 | 0 | | 2 | X | | 3 | 9 | | 4 | 8 | | 5 | 7 | | 6 | 6 | | 7 | 5 | | 8 | 4 | | 9 | 3 | | 10 | 2 | For example, if the remainder is 2, the check code is X. #### Example Suppose we want to generate a fictitious ID number: 1. **Address code**: Beijing, 110000 2. **Date of birth**: January 1, 1990, 19900101 3. **Sequence code**: 001 (indicating male) 4. **First 17 digits**: 11000019900101001 5. **Calculate the check code**: ``` (1×7) + (1×9) + (0×10) + (0×5) + (0×8) + (1×4) + (9×2) + (9×1) + (0×6) + (1×3) + (0×7) + (0×9) + (1×10) + (0×5) + (0×8) + (0×4) + (1×2) = 7 + 9 + 0 + 0 + 0 + 4 + 18 + 9 + 0 + 3 + 0 + 0 + 10 + 0 + 0 + 0 + 2 = 62 ``` 62 ÷ 11 = 5 remainder 7 → The check digit is 5 (according to the table, remainder 7 corresponds to 5) 6. **Complete ID number**: 110000199001010015 ### Notes 1. **Legality**: The above example is a fictitious number. Please ensure the legality and authenticity of the ID number when using it. 2. **Privacy protection**: Do not illegally collect, use or disseminate other people's ID numbers to protect personal privacy and comply with relevant laws and regulations. 3. **Update standard**: The generation rules of ID numbers are based on the standards as of 2023. There may be adjustments in the future. Please refer to the latest official information. If you need to know the personal identification number generation rules of other countries, please provide more information and I will do my best to answer you.