Your card number is carefully structured. The very first digit is what’s known as the major industry identifier. A 4 means ...

All mainstream credit card numbers obey a mathematical trick designed to catch the most common typos. It’s called the Luhn algorithm, named after IBM researcher Hans Peter Luhn, who patented it in ...

CVV stands for card verification value. It’s a three- or four-digit number found on most debit and credit cards. There are several other acronyms for this security feature within the industry.

If you cannot stop automatic payments from hitting your credit card, you might cancel that card and get a new number. However, when Kevin Patterson tried that, his credit card company gave his new ...