What is the difference between an abstract class and an interface?

Marker interface in Java ?

Why we use interfaces in java

Can a interface extend another interface?

Can abstract class implements another interface ?

Can you inherited multiple interfaces?

Can an Interface have a class?

What is nested interface ?

When can an object reference be cast to an interface reference?

Can we define private and protected modifiers for variables in interfaces?

What is marker interface in java?

Can an Interface be final in java?