Why do we need Abstract factory design pattern

abstract-factorydesign-patterns

Most of the definition says:

An abstract factory provides an
interface for creating families of
related objects without specifying
their concrete classes

What is the use of Abstract Factory Pattern as we can achieve the task via creating object of concrete class itself. Why do we have a factory method that creates object of Concrete class?

Please provide me any real life example where I must implement abstractFactory pattern?