Need font code info.

[D1830@AppleLink.Apple.COM (Jack Swisher & Assoc, M Wimble,PRT)]

Regarding font codes:
 
p55 of the manual says,
"They can be translated into font specs explicitly"
 
Oh?  How?  Also, if I want font-info, do I somehow construct a font spec to
feed to font-info or can I somehow use the font code value directly?
 
Finally, what is the format of the font code numbers?  Oh, I can make a guess,
but I'd rather know explicitly what I'm looking at - what is guaranteed to work
in the future?  For instance, given a font code, how would I enable bold and
italic and change the mode to :notpatxor?
 
What haven't I asked about font codes that I should have?
 
Thanks,
Michael Wimble
Sunnyvale, CA.
D1830