>I have been reading about interfaces, and I understand the concept, but my question is "So What?" I just don't see them being helpful other than to enforce standards. Should all of my classes have an interface? What does that gain me?
>
>Implementing interfaces is one way to implement multiple inheritance. Your subclass can inherit both from a superclass and one or more different interfaces.


We have this argument here at work all the time. You can simulate quasi-multiple inheritance using interfaces.