The purpose of interfaces continued

Question

OK so I gather that Interfaces are a way to enforce that an object implements a certain amount of functionality, without having to use inheritance. Kind of like a contract.

Answer 1

You are confusing interfaces and inheritance. They are different concepts and can complement to each other. If all the eat methods are only slightly different, then you can create a base class which will contain the common code and will be invoked from the subclasses through overriden methods which add the different parts. The base class can still implement the interface. Hope it is clear.