What exactly is meant by 'CompactFlash' in the context of flash memory?
Compact Flash is a memory card standard which defines the size of the card, the type of connector, the electrical signals on the connector, and the protocol to be used to read and write to the card. Internally the card will have 1 or more memory IC's that store data. These IC's can be constructed using a technology called either NOR or NAND flash. Originally Compact Flash cards used NOR flash memory, but nowadays they all use NAND flash. From the end users perspective it is irrelevant which technology is used: the Compact Flash card will operate the same way, although NAND flash cards will usually have much higher capacity.