ok I understand how the whole crypt function works with the salt. For a password I could store it encrypted in my DB using the crypt($password, $salt) command and just gcome up with an process to develop the salt. My question is how do I get an encrypted string from my database (say a credit card) and actually decrypt it so that I can use the cc numbers? and do any of you store credit cards in a system... if so, how do you do it?