The camera uses compact flash cards.
The camera will read both the reguarl compact flash cards and the USB comapct flash cards.
Sadly, the camera has no port that a new mac can easily use, so you need an external card reader.
A USB reader will read only USB Compact Flash cards, not the other kind.
try macmall or even Apple.com to see exaplmes of card readers. They are typically sub $20 US