Abstract class is a special type of class which cannot be instantiated and acts as a base class for other classes. Abstract class members marked as abstract must be implemented by derived classes.
A Deep Dive into C# Abstract Class
An abstract class can be used as a base class and all other derived classes should be implemented the abstract class definitions. All the abstract methods should be implemented in all non-abstract classes using the keyword called an override. and after overriding, the abstract method is in the non-abstract class. we can derive this class in another class and again we can override the same abstract method with it ultimately. abstraction in c# guide.
