What is Inheritance?

In Object oriented programming, we can create a class by inheriting the structure of another class. This is known as inheritance. Here newly created class is known as child class and the class from which it creates is known as Parent class.

Note: Child classes are also known as Base class or super class.

Note: Child classes are also known as derived class or sub class.

Note: In java we use extends as a keyword to implement the concept of inheritance.

How many types of Inheritance are possible?

There are 5 types of inheritance are possible

1. Simple or single Inheritance: Here one derived class inherits from only one base class.
   
   

   class Human
   {
   ....
   ....
   ....
   }
   class Indian extends Human
   {
   .... 
   .... 
   ....
   }

   

2. Multilevel Inheritance: Here one derived class inherits from a class, after than another class also inherits from the said derived class. The Super class for one is sub class for the other.
   
   

   class Human
   {
   ....
   ....
   ....
   }
   class Indian extends Human
   {
   .... 
   .... 
   ....
   }
   class Bengali extends Indian
   {
   .... 
   .... 
   ....
   }

   

3. Hierarchical Inheritance: Here more than one class derived from a single base class.
   
   

   class Human
   {
   ....
   ....
   ....
   }
   class Indian extends Human
   {
   .... 
   .... 
   ....
   }
   class Bangladeshi extends Human
   { 
   .... 
   .... 
   ....
   }
   class Pakistani extends Human
   { 
   .... 
   .... 
   ....
   }

   

4. Multiple Inheritance: Here one class derived from more than one base class
   

   

5. Hybrid Inheritance: It is a combination of Hierarchical and Multilevel Inheritance.

   

Note: Multiple and Hybride Inheritances are not supported in java by class. We can implement it by the interface.

Note: We can Alter Or Add any propery of Super class in sub class but can not delete any property.