class HelloWorld   // file must be called HelloWorld.java
{

       public static  // pure magic
       void main  ( String [] args  )  // method signature
       {
           // in the System object, get the out object, invoke
           // its println method with argument "Hello World",
           // which is a string literal
           System.out.println("Hello World") ;

           // integer literals, operators on literals
           System.out.println( 2 + 3 ) ;  // plus operator on integer type
           System.out.println( "2" + "3" ) ; // plus operator on String type
       }
}