can someone please tell me why is it recommended to use interface as datatype ??

I’m trying to understand the best practices for designing robust and maintainable software systems in Java. One concept that I’ve come across is the recommendation to use interfaces as data types instead of base classes. However, I’m struggling to understand the reasoning behind this approach.

From my understanding, using an interface as a data type allows for more flexibility and polymorphism, as it enables me to work with any class that implements the interface. But I’m not convinced that this is the only reason, and I’d like to know more about the benefits of this approach.

Can someone explain why using interfaces as data types is preferred over using base classes? How does this approach improve code quality and respect the SOLID principles of object-oriented design?

I’ve tried to research this topic, but I’m still unclear about the advantages of using interfaces as data types. I’d appreciate any insights or examples that can help me understand this concept better.