The CVV2 number

This is the F. A. Q. section of the Sfinco.net website.
The title was "What is a CVV2 number?"

Answer: Credit card companies are continuously battling credit card fraud for Internet transactions. To that end, they now require online customers to verify their credit card by entering a CVV2 number when making Web purchases in addition to the credit card number and expiration date.
 
You can find the CVV2 number on the back of your MasterCard & Visa cards. It consists of the last three digits AFTER your credit card number in the signature area of the card. American Express users can find their card's CVV2 number printed above and to the right of the imprinted card number on the front of their cards.
 
To update your credit card information with your CVV2 number, login to your Account section and click the "Create/Change/Cancel A Standing Order" link under the "Misc." heading. Scroll down again, and click the link to "Change Personal Information". Scroll down and under the "PAYTYPE" heading enter your credit card's CVV2 number in the appropriate field. You can also click the CVV2 Number link to view a graphic showing you exactly where to find this number on your credit card. Click the Update Card button when you're finished.