The Personal Identification Number or PIN is a unique four-digit code assigned to the card account number and known only to you. Your PIN is the access code to your account for all PIN point-of-sale purchases and ATM transactions. Memorize this number and do not share it with anyone. Also, do not write it on the card. When creating a PIN, be smart about your selection. Avoid making it a commonly known number such as the last digits of your phone number or birth date.