Interface (Java)

An interface in Java is a way for different parts of a program to talk to each other. Think of it like two friends who only speak different languages. If they want to communicate, they need a translator - that's what an interface does.

In Java, an interface is like a set of instructions that a class (which is like a blueprint for creating objects) can follow. It tells the class what methods (like instructions) it must have, and what those methods should do.

So let's say we have a program that needs to draw shapes. We can create a Shape interface that tells classes what methods they need to implement to be able to draw shapes. It might say something like: "Any class that wants to draw a shape must have a draw() method, and that draw() method should take a graphics object as an argument."

Now when we create a subclass of Shape, like Circle or Square, we know that they will both have a draw() method that can be called to draw the shape.

In summary, an interface is like a translator between two different parts of a program. It provides a set of instructions (methods) that a class must implement to be able to communicate with other parts of the program.