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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>
/* Any text in between these two characters is a block comment.
Block comments, unlike inline comments, can span multiple lines.
Comments are ignored by the compiler and will not be executed.
*/
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int main(void)
{
printf("Hello, World\n"); // text after two slashes '/' are called inline comments.
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return 0;
}
```
## Explanation
* The `#include <stdio.h>` is a preprocessor directive. This directive tells preprocessor to include the contents of `stdio.h` (standard input and output) file in this file.
* 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 compiler will generate an error during compliation of the program.
* The execution of a C program starts from the `main()` function. We write `int` before it to specify that the program returns a integer value.
* The `printf()` is a library function to send formatted output to the standard output stream, most commoly the screen. In this program, the `printf()` displays `Hello, World!` text on the screen.
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* `\n` is used here to take the cursor to the next line. Hence, if we print anything after this command, it will be printed on a new line.
* The `return 0;` statement is the "Exit code" of the program. In simple terms, the program ends with this statement or it signifies that function does not return any value.
## 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.