C Language

Part of the Fundamentals section of Coddy's C journey — lesson 1 of 63.

C is a powerful and efficient programming language that provides low-level access to memory while maintaining high performance. It's ideal for system programming, embedded systems, and operating systems, offering fine-grained control over hardware and memory management.

Here is what a basic C program looks like:

#include <stdio.h> — includes the standard input/output library so you can use functions like printf.

int main() { — defines the main function, which is where every C program starts running.

printf("Hello, World!\n"); — prints the text Hello, World! to the screen. The \n moves the cursor to a new line.

return 0; — tells the operating system the program finished successfully.

} — closes the main function.

Press Run to see your first C program in action!

Challenge

Beginner

Press the run code button to run your first code in C.

Cheat sheet

A basic C program looks like this:

#include <stdio.h>

int main() {
    printf("Hello, World!\n");
    return 0;
}

#include <stdio.h> — includes the standard input/output library so you can use printf.
int main() — the main function where your program starts running.
printf(...) — prints text to the screen.
\n — moves the cursor to a new line.
return 0; — signals that the program finished successfully.

Try it yourself

#include <stdio.h>

int main() {
    printf("Hello C!\n");
    return 0;
}

All lessons in Fundamentals

1Introduction

C LanguageHello World!Comments Basic Program Structure

4Control Flow

If Statement If - Else Else-If Switch Case Ternary Conditional Operator Recap Challenge Nested If - Else

7Functions

Declare a Function Return Types Parameters Recap Challenge #1 Recursion Basics Function Prototypes Recap Challenge #2