Abstraction in object oriented programming
It is a process for showing necessary details and hiding implementation details from the user called abstraction .
it can be used to make flexible ,maintainable and secure application
with the help of abstraction we can create a flexible application, flexible means in the future suppose we have to make some changes in our application then we don't need to change overall application .
in terms of security we hide the implementation details therefor our application is more secure than the other application by using abstraction
How we can implement abstraction
We implement abstraction using Abstract class or interfaces
by using this terms we can resolve design level issue
Abstract class = it contain abstract methods and non-abstract methods , the method which doesn't have body or implementation is called abstract method
there should be at least one abstract method in abstract class
interfaces \= It contains only all abstract methods .