public void helloWorld() {
        System.out.println("Hello world!");
        // A lot of code can be inside methods :)
        // A lot of code can be inside methods :)
        // A lot of code can be inside methods :)
        // A lot of code can be inside methods :)
        // A lot of code can be inside methods :)
        // A lot of code can be inside methods :)
        // A lot of code can be inside methods :)
        // A lot of code can be inside methods :)
    }
public void helloWorld()