Class- A Class is a template of objects which can handle more than one characteristics . It has attributes and methods.
Objects- Object is an real time entity in the world. It is the instances on classes and hold some data.
Association- Relating two classes or relation between two classes is called as Association.
Aggregation- One class using the instances on other class is know as Aggregation.
Composition- when one class data is related or will affect other class data is known as composition. Eg: when one class data is deleted the data pertaining to that in another class will be deleted.
Abstraction- Extracting the essential details or data while ignoring the unwanted data.
Encapsulation( known as information hiding)-
Restricts the visibility of attributes and methods t.
Every object has an interface which shows how the objects interact with each other.
Implementation part is hidden so that the process of interaction between the objects is made invisible to others.
Identical methods behave differently in different classes.
With the help of an interface it enables to address methods with same name to different objects.
The signature or the definition of the method is always the same but the implementation is different for different classes.
Deriving a new class from the existing class
Can inherit the data and methods of the super class
Can overwrite the existing methods and can also add new ones.