what do last 4 digits of social security number mean
Social Security number The last four digits are serial numbers. They represent a straight numerical sequence of digits from 0001 to 9999 within the group.
Card security code The card security code is typically the last three or four digits printed, not embossed like the card number, on the signature strip on the back of the card. On American Express cards, the card security code is the four digits printed (not embossed) on the front towards the right. The card security code is not encoded on the magnetic stripe but is printed flat.