What is the meaning of the numbers in the bank card number?
The first number on the bank card (credit card) represents the bank
System attributes of bank cards:
2.3.2 Card number structure
American Express - The 3rd and 4th digits indicate the card type
and currency, The 5th to 11th digits represent the card account number, the 12th to 14th digits are the serial number of the card in the account, and the 15th digit is the check digit.
Visa -The 2nd to 6th digits are the bank code, the 7th to 12th or 15th digits are the card account number, the 13th or 16th digit (i.e. the last one)
One digit) is the check digit.
MasterCard - Digits 2 and 3, Digits 2 to 4, Digits 2 to 5
Digit or 2 The 6th digit is the bank code (depending on the 2nd digit: 1, 2, 3 or something else). The bank code is followed by the 15th digit. The 16th digit is the card account number, and the 16th digit is the check digit. What is the meaning of each digit in the phone number
The first group of fixed-line telephone numbers represents the province, the second group represents the office number, and the others represent The number of the phone number.
Our mobile phone number is called MSISDN
MSISDN=CC (country code) + NDC (7 digits) (domestic destination code) + SN (4 digits) (user number)
p>If the country code CC is removed, it becomes the domestic number of the mobile station, which is what we usually call the mobile phone number.
NDC includes the access number and HLR identification number.
The access number is what we usually call 139, 138, 137. . . . . . What remains is the HLR identification number, which represents the HLR to which the user belongs and also represents the local network number of the mobile service. What do the numbers on food barcodes mean?
Take the barcode 6936983800013 as an example
This barcode is divided into 4 parts, from left to right:
Digits 1-3: ***3 digit, corresponding to 693 of this barcode, is one of the country codes of China. (690--695 are all Chinese codes, assigned internationally);
Digits 4-8: ***5 digits, corresponding to 69838 of the barcode, representing the manufacturer code, applied by the manufacturer , allocated by the country;
Digits 9-12: ***4 digits, corresponding to 0001 of the barcode, representing the product code in the factory, determined by the manufacturer;
Digit 13 : ***1 digit, corresponding to the 3 of the barcode, is the check code, which is calculated from the previous 12 digits according to a certain algorithm.
The food sold in stores now has a food barcode. Generally speaking, food barcodes are divided into 4 parts, which are judged from left to right. The order is fixed. It consists of 13 numbers and is divided into several groups. For example, 6942722500168
①The first three digits in the first group: 694, which is one of China’s country codes.
Numbers in the range of 690-695 are assigned to China by the international community.
② The second group of 4-8 digits:
27225. These five numbers represent the manufacturer. They are five numbers assigned to merchants by the state and are exclusive to merchants.
③The third group of 9-12 digits: 0016. These four numbers are the product code in the factory. This code is given by the manufacturer according to its own situation. It has a relatively high degree of freedom, but it is also anti-counterfeiting. The most important code.
④The last digit of the fourth group: 8. This is the check code of the barcode. This check code is calculated by a random calculation method and is calculated based on the previous 12 numbers. result.
Looking at the current food barcodes, we already have very comprehensive information and very precise verification and calculation methods, which are an important means for us to protect our food safety.