What is difference between abstract and interface?

Answer»

Abstract	Interfaces
Abstract classes cannot be implemented.	The Interfaces needs to be implemented.
They are models which can have some METHODS to be used by all the inherited children.	It is a contract, where the RECEIVER is ASKING a SPECIFIC type of input and SENDER agrees to send it that way.
Abstract classes can have private methods.	Interfaces can not have private methods. All the plans are public.

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