Understanding the purpose of Abstract Classes in Java

Question

Suppose I have two Classes, A and B. The A class is defined as abstract, while B extends this abstract class, and finally i test the result and both classes are part of same

Answer 1

Abstract Classes allow you to store base level implementations (inheritance), while also producing a contract that guarantees inherited classes will implement specific functionality (interface) on their own...

While there will never be a instance of an Abstract Class, you can store shared functionality between inheritors...

I've always thought of them as Interfaces that allow base level implementations of certain methods...