Is Maxima modular?...(and/or How learn source code?...)

Richard

> In fact, most of the underlying code that can be
> thought of as neatly modular in nature is modular
> already. If you only provide (say) polynomial arithmetic,
> then you can be pretty clean.

How would you recommend one learn about the underlying
architecture of Maxima??  I'm looking at the
src directory of Maxima and I see a ton of files.
How can I break thru and get a better understanding
of the architecture??

My only paradigm for attacking complex programs I
know is "divide and conquer".  I'm tempted to somehow
put lots of these files in separate directories
or at least associate groups of them in my head.
I feel like best idea is to 
treat many of them as "black boxes" somehow.

How can I get a handle of this modular nature of Maxima???

I'm all ears.

Chris