Abstract classes represent a powerful tool at our disposal when following the OOP paradigm. Properly implemented, they enhance our code and make it more robust, secure, and maintainable.
Interfaces in Java define behaviors, which are expressed as a group of methods in their bodies. They establish a well-defined API contract between two parties and promote loose coupling.
Java classes and objects are cornerstones of the Object-Oriented Programming (OOP) model that allows us to represent real-world concept and entities in our programs.