Can someone explain the benefits of polymorphism?

Question

So I understand pretty much how it works, but I just can\'t grasp what makes it useful. You still have to define all the separate functions, you still have to create an instanc

Answer 1

A good example of useful polymorphism is the .NET Stream class. It has many implementations such as "FileStream", "MemoryStream", "GZipStream", etcetera. An algorithm that uses "Stream" instead of "FileStream" can be reused on any of the other stream types with little or no modification.