• System.out.println
• System
• println

Printing Hello World on the screen is a bit more complex in Java than in many of the so-called scripting languages, but still it is probably the most simple thing you can do in the language. So let's see it.

Create a file with a name like HelloWorld.java . The extension .java is important , so is the name. In the file we create a class with the same name as the name of the file.

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello World");
    }
}

$ javac HelloWorld.java       # Compiles the file and creates HelloWorld.class
$ java HelloWorld
Hello World