where does "CARD18" come from?

[Dave Airlie]

>
> I was wondering where the names of various data types listed here may
> come from:
> http://www.x.org/wiki/XSessionManagementProtocol#Data_Types
>
> Most of them are clear, but these ones picked my interest:
>
>  CARD8
>  a one-byte unsigned integer
>
>  CARD16
>  a two-byte unsigned integer
>
>  CARD32
>  a four-byte unsigned integer

If memory serves, it just means Graphics card.

Dave.