credit card conventional wisdom

[Rich Salz]

>There is in fact a distinction between "card present" and "card not present"
>transactions. AMEX cards for example have an extra group of four digits which 
>are not part of the embossed card number. They are used as additional 
>verification to prove that a card is present.

So the run-it-through-the-mechanical-device is treated as card not present?
	/r$