What and where is the credit debit Card Verification Number CVV?

For your online safety and security, we require that you enter your credit or debit card's
verification number CVV before we can process your payment. As shown below,
the Card Verification Number CVV is the last three digit number printed
on the signature panel located on the back of your card.
The CVV is a security feature that allows Tradition of London and your credit card issuer
to identify you as the cardholder and provide you with additional security against fraud