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"Hello, World!" program

While minimal test programs such as this existed since the development of programmable computers, the tradition of using "Hello world!" as the test message was probably started by its use as an example program in the book The C Programming Language, by Brian Kernighan and Dennis Ritchie.

Here are some examples in different languages:

• Ada

   with Ada.Text_Io; use Ada.Text_Io;
   procedure Hello is
   begin
      Put_Line ("Hello world!");
   end Hello;

• Assembly (x86 CPU, DOS, TASM syntax)

   MODEL SMALL
   IDEAL
   STACK 100H

   DATASEG
       HW      DB      'Hello, World!$'

   CODESEG
       MOV AX, @data
       MOV DS, AX
       MOV DX, OFFSET HW
       MOV AH, 09H
       INT 21H
       MOV AX, 4C00H
       INT 21H
   END

• BASIC

   PRINT "Hello world!"

• BCPL

   GET "LIBHDR"

   LET START () BE
   $(
       WRITES ("Hello World!*N")
   $)               

• Brainfuck

   ++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<
   +++++++++++++++.>.+++.------.--------.>+.>.

• C

   #include <stdio.h>
   int main(void)
   {
       printf("Hello world!");
       return 0;
   }

• C++

   #include <iostream>
   int main()
   {
       std::cout << "Hello world!" << std::endl;
       return 0;
   }

• COBOL

   IDENTIFICATION DIVISION.
   PROGRAM-ID.     HELLO-WORLD.

   ENVIRONMENT DIVISION.

   DATA DIVISION.

   PROCEDURE DIVISION.
   DISPLAY "Hello, World".
   STOP RUN.

• Common Lisp

   (format t "Hello world!~%")

• Eiffel

   class HELLO_WORLD

   creation
       make
   feature
       make is
       local
               io:BASIC_IO
       do
               !!io
               io.put_string("%N Hello World!!!!")
       end -- make
   end -- class HELLO_WORLD

• Forth

   .( Hello world!)

• INTERCAL

  PLEASE DO ,1 <- #13
  DO ,1 SUB #1 <- #238
  DO ,1 SUB #2 <- #112
  DO ,1 SUB #3 <- #112
  DO ,1 SUB #4 <- #0
  DO ,1 SUB #5 <- #64
  DO ,1 SUB #6 <- #238
  DO ,1 SUB #7 <- #26
  DO ,1 SUB #8 <- #248
  DO ,1 SUB #9 <- #168
  DO ,1 SUB #10 <- #24
  DO ,1 SUB #11 <- #16
  DO ,1 SUB #12 <- #158
  DO ,1 SUB #13 <- #52
  PLEASE READ OUT ,1
  PLEASE GIVE UP

• Java - console program

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

• Java - applet

   import java.applet.*;
   import java.awt.*;

   public class HelloWorld extends Applet {
     public void paint(Graphics g) {
       g.drawString("Hello, world!", 20, 20);
     }
   }

• Pascal

   program Hello;
   begin
       writeln('Hello world!');
   end.

• Perl

   print "Hello world!";

• PHP3

   <?php
       echo "Hello world!";
   ?>

• PL/I

   Test: procedure options(main);
      declare My_String char(20) varying initialize('Hello, world!');
      put skip list(My_String);
   end Test;

• Python

   print "Hello world!"

• Ruby (similarity to Perl version is not accidental)

   print "Hello world!"

• Smalltalk

   Transcript show: 'Hello world!'

• SQL

   SELECT 'Hello world!' FROM DUAL;

• Turing

   put "Hello world!"

• Visual Basic

   MsgBox "Hello, world!"

Graphical User Interfaces

Libraries and APIs are also frequently tested by means of "Hello, world" programs. For example, a GUI library can be tested by a program that draws a window with the text "Hello, world." Here is an example of a standalone Java application that does this (which is necessarily more complex than an applet or simple text application):

   import java.awt.*;
   import java.awt.event.*;

   public class HelloFrame extends Frame {
     HelloFrame(String title) {
       super(title);
     }
     public void paint(Graphics g) {
       super.paint(g);
       java.awt.Insets ins = this.getInsets();
       g.drawString("Hello, World!", ins.left + 25, ins.top + 25);
     }
     public static void main(String args [])
     {
       HelloFrame fr = new HelloFrame("Hello");

       fr.addWindowListener(
         new WindowAdapter() {
           public void windowClosing(WindowEvent e)
           {
             System.exit( 0 );
           }
         }
       );
       fr.setResizable(true);
       fr.setSize(500, 100);
       fr.setVisible(true);
     }
   }

Many more examples can be found at Hello, World Page!.

See also: Just another Perl hacker