Difference Between Abstract Class and Interface in Object-Oriented Programming

Abstract classes and interfaces are important concepts in object-oriented programming. Here are the key differences between them:

• Definition: An abstract class is a class that cannot be instantiated and may contain both abstract and non-abstract methods. Interfaces, on the other hand, are a collection of abstract methods and constants, but cannot have any concrete implementation.
• Multiple Inheritance: A class can only inherit from a single abstract class, but it can implement multiple interfaces. This means that interfaces support multiple inheritance while abstract classes do not.
• Implementation: Abstract classes can provide a partial implementation of the methods, while interfaces can only declare the methods that must be implemented by the classes that implement the interface.
• Usage: Use an abstract class when you want to provide a common base implementation for derived classes and use an interface when you want to define a contract for classes that implement it.

Overall, abstract classes and interfaces serve different purposes in object-oriented programming and understanding their differences is crucial for designing effective and flexible software systems.