I'm struggling to grok this myself at the moment (and I think I'm reading the same book as the OP...).
It seems to me that interfaces simply enforce a "contractual" obligation on classes that implement the interface to implement functions/properties that appear in the interface. Yet, isn't it the case that classes/objects which implement the interface can do so in a unique fashion since the implementation is not defined?
There is no actual inheritance involved is there?
