[Zope] ZClass Products question - sub-classing

[Jeffrey Franks]

Hi,

How do I determine the classes I should subclass when
creating a ZClass object?

I know what my new object is going to do generally, but how
is the design decision made regarding which Zope base classes
to sub-class from. We're obviously talking about interfaces
and what the new object is expected to do.

As a newbie, I know the names of the base classes, but have
little understanding of what their interfaces allow them to
do. Where do I get information about this?

As an example: In the book "Zope Bible" page 478, the authors
provide a simple application of FAQManager ZClass. The reader
is told to sub-class from ZClasses: ObjectManager and
OSF: Folder classes.

How is such a design decision made when creating a new thingy?

-- 
Jeffrey L. Franks  (Web)  http://www.motiftools.org
                   (Mail) jfranks@quik.com