OOP is used to structure a software program into simple, reusable pieces of code blueprints (usually called classes), which are used to create individual instances of objects.

Building blocks of OOP:

• Classes are where we create a blueprint for the structure of methods and attributes. Individual objects are instantiated or created from this blueprint. For example, we can look at Duck class covered in class activity.
• Objects are instances of classes created with specific data, for example rubber duck is an instance of duck class. It is crucial to remember that class is a template for modeling (a duck in our example), and an object is instantiated from the class representing an individual real-world thing (a rubber duck in our example).
• Methods perform actions; methods might return information about an object or update an object’s data. The method’s code is defined in the class definition. In simple terms, methods represent behavior. For our Duck example, ducks had methods like fly() and quack(). Duck’s had different behavior. Rubber duck did not fly and did not quack but squeaked. These behaviors are specified in methods.
• When objects are instantiated, individual objects contain data stored in the Attributes. State of objects depend on data in attribute. For example, Rubber duck is handled differently than a mallard duck based on the information in attributes.

The four principles of OOP:

• Inheritance allows classes to inherit features of other classes. Basically, child classes inherit data and behaviors from parent class. In our example, Rubber duck inherited display() from duck class.

• Encapsulation is containing information in an object and exposing only selected information to other classes. Private methods and properties are accessible by other methods of the same class. Public methods and properties are accessible by methods of other classes too.

• Abstraction is using simple classes to represent complexity. It uses simple things to reduce complexity. Abstraction means that the user interacts with only selected attributes and methods of an object. Abstraction is used in interface. In FlyBehavior we had abstract fly() which was defined in concrete classes as flyWithWings or flyNoWay.

• Polymorphism uses inheritance. Objects can override shared parent behaviors, with specific child behaviors. In method overriding, a child class can provide a different implementation than its parent class. In method overloading methods or functions may have the same name, but a different number of parameters passed into the method call.

Abstraction reduces complexity and constant overriding of method. Inheritance gives reusable structure across program. Polymorphism allows for class-specific behavior and objects of different types to be passed through the same interface. Encapsulation helps us prevent unwarranted change of important data by developers. Also, Prevents greater security risks like phishing that we face today.Advantages of OOP will never die out. Therefore, I have written this blog explaining OOP and I hope it has been useful.

Sources

https://codecoda.com/en/blog/entry/object-oriented-programming

From the blog CS@worcester – Towards Tech by murtazan and used with permission of the author. All other rights reserved by the author.