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Answered 2011-11-30 17:44:35

Assume a "simple" class be a class without the keyword "abstract".

You cannot create an instance of an abstract class. An abstract class is intended to be inherited from (to be extended or derived from).

A "simple" class is a class that an instance can be created from (via new operator)

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If a class has one abstract method ,the class has to be an abstract class.Methods can be implemented in abstract class.Whereas a interface is like a abstract class...the only difference being that the methods are never implemented in Interface.


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A more prcise description of difference is as follows.... an interface is a specification of a set of methods that the implementation class must adhere to, while an abstract class is indeed an implementation class albeit a class that is not concrete, i.e., one cannot directly instantiate an abstract class.


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abstract class no defination used by derieved class where virtual base class is defination that can be overriden later on


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