freeCodeCamp/guide/english/c/hello-world/index.md

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---
title: Hello World C
---
## Hello World
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Probably the first line of text that everyone prints out on the console when one begins his/her remarkable journey of this endless programming world.
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To write on console you can use the function `printf()` contained in the library `include <stdio.h>`
```C
#include <stdio.h>
int main(void)
{
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//lines starting with this are called comments, so use them to write notes to the reader about your code!
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//this code prints "Hello World!"
printf("Hello World!\n"); //<-- the \n character prints a newline after the string
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return 0;
}
```
## Explanation
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* The `#include <stdio.h>` is a preprocessor command. This command tells compiler to include the contents of `stdio.h` (standard input and output) file in the program.
* The `stdio.h` file contains functions such as `scanf()` and `printf()` to take input and display output respectively.
* If you use `printf()` function without writing `#include <stdio.h>`, the program will not be compiled.
* The execution of a C program starts from the `main()` function.
* The `printf()` is a library function to send formatted output to the screen. In this program, the `printf()` displays `Hello World!` text on the screen.
* The `\n` in `printf` creates a new line for the forthcoming text.
* The `return 0;` statement is the "Exit status" of the program. In simple terms, program ends with this statement
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## Output:
```
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>Hello World!
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```
#### More Information
* Conventionally, the first ever program you write is the "hello world" program, be it in any language.
* This is because Brian Kernighan was the first to write "hello, world" program for the documentation of the BCPL programming language developed by Martin Richards.