When should you use abstract classes instead of interfaces?

[sumaiyakhatun26]

Let's repeat: abstract classes are needed to provide common functionality for several classes in one hierarchy. Interfaces are suitable if each class will implement methods independently.
Based on this, we understand the following: abstract classes should be used when a common implementation of hierarchically united classes is needed. And interfaces are suitable for disparate ones.

Conclusion: Abstract classes and methods are very powerful chinese overseas british databasetools that are really worth learning to use. They will help you create modular and understandable code that other developers can understand and appreciate.
When creating a group of related classes with common functionality, these are the tools you should turn to.