In this definition...
What is Hello World?
A Hello World program is a computer program that outputs or displays the message, “Hello, World!” This program can be created in most programming languages and is traditionally used to illustrate the basic syntax of the language.
Functionally, the Hello World computer program tells the computer to display the words “Hello, World!” In most cases, it’s the first program developers use to test a system. This program is simple to run, so if it doesn’t work effectively within the framework, it’s likely that more complex programs will also fail. Successfully displaying those two words shows the creator of the program that their code can compile, load, and run a program. With this test, they can also see the output.
The Hello World program has grown into a sort of tradition among developers through the decades, as most use it to signify the success of a completed program. The Association of Computing Machinery at Louisiana Technological University found approximately 200 versions of the program from different programming languages.
Uses of Hello World
Hello World holds little weight in evaluating a programming language and its constructs. It’s mainly used to ensure the compiler is in the path, the libraries are in the right place, and the build script is sane. But the program is used for a variety of other reasons, including:
Introduction to coding world
Hello World is typically the first program written by those learning to code and helps novice coders become acquainted with a new language. With this computer program as a foundation, developers can understand computer science principles and elements.
Beginners and professionals alike use Hello World when learning a programming language previously unknown to them to become familiar with the structure and syntax of the language.
Sanity test
This program can be used as a sanity test to ensure the components of the programming language (the compiler, development, and run-time environment) are correctly installed and that the operator understands how to use it.
Because the process of configuring a complete programming toolchain (a set of programming tools used to perform a complex software development task) is complex, a simple test such as Hello World is useful to serve as a baseline.
Proof of concept
Developers also use Hello World as a proof of concept that random code can’t be executed through an exploit where the original developers of the language did not intend the code to be executed. When seasoned programmers are configuring an environment or learning a new one, they verify that Hello World works correctly as the first step.
Debugging process
Coders use Hello World to ensure they’re editing the right aspect of a modifiable program at runtime and that it is reloading properly.
Basis for comparison
Developers can use Hello World as a basis for comparison. They compare the size of the program that the language generates and how much supporting infrastructure must exist in order for the program to execute.
History of Hello World
IMAGE: The iconic greeting conceived in 1978 by Brian Kernighan both new and experienced programmers are familiar with within the realm of computer code.
Small test programs have existed since the development of computers, but using the phrase “Hello, World!” as a test message began in the 1970s.
In 1972, Brian Kernigham worked at Bell Labs and was asked to write an internal manual for using the programming language B, a simplified version to an even older language, BCPL. Kernigham wrote the memorandum titled A Tutorial to the Language B. In this text, the first known version of the Hello World computer program is documented to illustrate external variables. It appears in section 7 — “External Variables” in the following form to demonstrate the piecing together of several char variables:
main( ) {
extrn a, b, c;
putchar(a); putchar(b); putchar(c); putchar(’!*n’);
}
a ’hell’;
b ’o, w’;
c ’orld’;
The next instance of “Hello, World!” appeared in another internal memorandum for Bell Labs in 1974, also written by Kernigham, titled Programming in C: A Tutorial. It appears in section 2 — “A Simple C Program”:
main( ) {
printf(“hello, world”);
}
Kernigham, along with Dennis Ritchie, then wrote one of the most widely read programming books, The C Programming Language in 1978. The “Hello, World!” example listed above in the 1974 memo appeared in this book, and it gained immense popularity because of it. It appears in section 1.1 — “Getting Started”.
Before Hello World, there was no standard program that was run first. After the program was invented, it spread quickly and became well-known by the late 1970s. When Kernigham was asked by Forbes why the words, “Hello, World!” were chosen, he states that while his memory is dim, he remembers watching a cartoon that showed an egg and a chick, in which the chick said, “Hello, world!”
The C Programming Language is one of the most popular programming books because of the success of the microcomputer PDP-11, which was introduced within the same timeframe as the book. The price point of the microcomputer was drastically lower than what computers had been in the past, meaning more people purchased the programmable computer. As more people bought the computer, more people read The C Programming Language, introducing readers to “Hello, World!” In the ‘80s and ‘90s, almost every C programmer owned a copy or referenced the book in some way.
Time to Hello World
Time to Hello World (TTHW) is the time it takes to create a Hello World program in any given programming language. This can be used as an indicator of the given program’s ease of use, assuming that if the Hello World program set up time is lengthy, it may be less approachable for new learners.
The concept of TTHW has been extended to APIs. It serves as an indicator of how simple it is for a developer unfamiliar with the API to get a basic example working. A faster time means the API is easier for new developers to adopt.
Variations
Hello world programs vary in complexity with each programming language. In some languages, such as scripting languages, the program can be written as a single statement. In other languages, such as low-level languages, multiple statements are required. As a general rule of thumb, programming languages that give the programmer more control over the machine will result in a more complex Hello World program.
Hello World code for top 10 programming languages
#include <stdio.h>
int main() {
// printf() displays the string inside quotation
printf("Hello, World!");
return 0;
}
class HelloWorld {
public static void main(String[] args) {
System.out.println(“Hello, World!”)
}
}
using System;
class Program
{
public static void Main(string[] args)
{
Console.WriteLine("Hello, World!");
}
}
#include <iostream>
int main() {
std::cout << “Hello, World!”;
return 0;
}
print(“Hello, World!”)
Module HelloWorld
' every console app starts with Main
Sub Main( )
System.Console.WriteLine("Hello, World!")
End Sub
End Module
document.println("Hello, world!");
Or
alert("Hello, world!");
Or
document.writeln("Hello, world!");
title Hello World Program dosseg .model small .stack 100h .data hello_message db 'Hello, world!',0dh,0ah,'$' .code main proc mov ax,@data mov ds,ax mov ah,9 mov dx,offset hello_message int 21h mov ax,4C00h int 21h main endp end main
<?php Print "Hello, World!"; ?> <?php Echo "Hello, World!"; ?>
begin
dbms_output.put_line('Hello, World!');
end;
Other programming languages’ Hello World code
#!/usr/bin/perl print "Hello World!n";
puts "Hello, world!"
object HelloWorld extends App {
println("Hello, world!")
}
Response.Write("Hello World!");
Common Lisp
(print "Hello, world!")
main = putStrLn "Hello, world!"
package main
import "fmt"
func main() {
fmt.Println("Hello, world!")
}
with Ada.Text_IO;
procedure Hello is
begin
Ada.Text_IO.Put_Line ("Hello, world!");
end Hello;
IDENTIFICATION DIVISION. PROGRAM-ID. HELLO-WORLD. PROCEDURE DIVISION. DISPLAY 'Hello, world'. STOP RUN.
program HelloWorld; begin writeln( 'Hello, world!' ); end.
PROGRAM HELLO PRINT *,'Hello, world' STOP END
With modern coding languages becoming increasingly complex, the Hello World program becomes increasingly important. It provides a simple, standardized process to configure an environment as both a test and a teaching tool.
