>By the way, interfaces, as used frequently, do not aid in OO design/development at all. Interfaces, in the most commonly used way, are just a workaround to the problems that arise using types in an OO language.
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>What you described can be done with abstract classes, but what if all the objects aren't in the same class hierarchy?
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>Interfaces are used extensively in the .NET Framework. Interfaces provide a good mechanism for implementing contracts on objects - they guarantee that an object will support specific PEMs of the named interface.
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>Interfaces also simplify distributed computing (specifically, remoting), where code in one domain must work with classes in different domains. Interfaces also allow us to implement polymorphism, when multiple inheritance doesn't exist.
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>Kevin

I know what an interface is.