Abstract classes and interfaces in Java serve fundamentally different purposes. Learn the differences between these Java language elements and how to use them in your programs.

Why does Java's standard class library contain empty interfaces like Cloneable and Serializable? Find out why in this sixth installment in the "Object-oriented language basics" series.

Interested in Java functional programming? The first place you need to start, especially if you use the Streams API, is with this Java Function interface example.