>Sorry for the ignorant newbie question....what exactly is the difference
>between the blue and yellow boxes?  I thought this was a NeXT thing....

The coloured boxes are code terms used to describe various parts of 
Apple's next operating system.

Yellow box = the OpenStep application libraries
Blue box = a modified version of MacOS that runs inside another OS as an 
independent program
Grey box = Carbon = a library that acts like a buzzword-enabled MacOS 
Toolbox

-Mars