Hello world program facts for kids

A "Hello world!" program running on Sony's PlayStation Portable as a proof of concept.

A Hello world program is a very simple computer program. It is often the first program a new computer programmer learns to write. Its main job is to show the words "Hello, World!" on a screen. Programmers also use it to check if their programming tools are set up correctly. This basic program can be written in almost every programming language out there.

What is a "Hello World" Program?

The "Hello world" program is like a first step into the world of coding. It's a tradition for people learning a new programming language. By writing this simple program, they can make sure everything is working. It confirms that the language's tools, like a compiler, are ready to turn their code into something the computer understands.

Why is "Hello World" Important?

This small program is important for several reasons:

• First Test: It helps new programmers see immediate results from their code. This can be very exciting and encouraging.
• Tool Check: It's a quick way to test if the programming environment is set up right. If "Hello, World!" appears, you know the basic tools are working.
• Learning Basics: Even though it's simple, it teaches fundamental ideas. These include how to write code, save it, and run it.
• Universal Example: Almost every programming language has its own version of "Hello world." This makes it a common starting point for coders worldwide.

How Does a "Hello World" Program Work?

At its core, a "Hello world" program tells the computer to display specific text. Different programming languages have different ways of saying "show this text." But the goal is always the same. Let's look at a couple of examples.

"Hello World" in C Language

The C programming language is a very powerful and widely used language. Here is how you would write "Hello World" in C:

#include <stdio.h>
int main(int argc, char* argv[])
{
     printf("Hello World");
     return 0;
}

In this code:

• `#include <stdio.h>` tells the program to include a standard library. This library helps with input and output, like printing text.
• `int main()` is where the program starts running.
• `printf("Hello World");` is the command that actually prints "Hello World" to the screen.
• `return 0;` tells the computer that the program finished successfully.

"Hello World" in Pascal Language

Pascal is another programming language. It was designed to be easy to learn and read. Here is the "Hello World" program in Pascal:

program helloworld;
begin
     WriteLn('Hello World');
end.

In this Pascal code:

• `program helloworld;` gives the program a name.
• `begin` and `end.` mark the start and end of the program's main part.
• `WriteLn('Hello World');` is the command that writes "Hello World" to the screen. `Ln` means it will also move to the next line after printing.

Images for kids

• 

  "Hello, World!" program by Brian Kernighan (1978)

• 

  A "Hello, World!" message being displayed through long-exposure light painting with a moving strip of LEDs

See also

In Spanish: Hola mundo para niños