How do abstract classes differ from Interfaces? - Delphi

How do abstract classes differ from Interfaces?

- Abstract classes provide different placeholder methods and they have their classes extending them. Whereas, Interfaces are not classes but it, also uses the placeholder methods.

- Abstract classes are extended by any other class and the functions are extended to provide more functionality. Whereas, interfaces, are, not extended by any other class.

- Abstract class gets inherited by the new class or extended by an existing class. Whereas, interfaces placeholder’s, methods are being implemented in the class.

- Only one abstract class can be extended by another class. Whereas, multiple, interfaces can be implemented in one class.