Difference between card reader & common interface

[Adam_UK]

Looking at Spiderbox spec.:

It has:

- 2 Slots common interface for Viaccess, Irdeto, Cryptoworks, Nagravision, Conax, Mediaguard and etc.
- 1 Slot smart card

Can somebody explain what is the difference between common interface & smart card I assume both capable of reading official and unofficial cards?

Cheers

[Superman]

COmmon Interface is CI Modual, basically its for CAMS, smart card slot are self explanatory, they are card reader.