Factory Method and Abstract factory Design Pattern:-

Factory Method:-  Define an Interface/Method for Creating Objects.(Create one Product only)

Abstract Factory Method:- Define an interface/Method/Object for Creating families of related or dependent object, necessarily an Object.(Create Set of Many Products/Create one product at least)

Level of Abstraction is one level higher in Abstract Factory, it often uses Factory Method to create the products in factories.

 

For Factory Pattern, Each classes derived from Factory Class(like ConcretFactoryA1,ConcretFactoryA2,ConcretFactoryB1,ConcretFactoryB2)  will return one object only. But for abstract factory pattern, creates family of related object.

Simple Factory, Where one static method which returns class pointer can be used to know the type of object at run time. This can be visualized as virtual constructor which is not possible in normal scenario.

Code structure will be added for the same in few days..