Introduction Writing your first C program is an exciting milestone in your coding journey! This is where theory meets real action. Why Study This Topic? Think of C programming like building with LEGO blocks. Your very first program is the foundation block — once you place it right, you can build anything from small gadgets to rockets (well, almost!). Creating and running a basic program builds your confidence and sets the stage for bigger projects. What Will Be Covered? How to write a basic "Hello, World!" program How to save and compile the program How to run your first executable file Common beginner mistakes and how to fix them Steps to Write Your First C Program Open Your IDE or Text Editor You can use Code::Blocks, Visual Studio Code, or even a simple Notepad. Type the Program Here’s a classic "Hello, World!" program: #include <stdio.h> int main() { printf("Hello, World!\n"); return 0; } Explanation: #include <stdio.h>: Tells the compiler to include standard input/output functions. int main(): Main function where the execution begins. printf: Prints text to the screen. return 0;: Signals that the program ended successfully. Saving the File Save your file with a .c extension.Example: hello.c Compiling the Program Using GCC: Open your terminal or command prompt and run: gcc hello.c -o hello This command tells GCC to: Compile hello.c Output a file named hello (or hello.exe on Windows) 🚀 Running the Program On Windows: hello On macOS/Linux: ./hello ✅ If everything is set up correctly, you should see: Hello, World! Common Beginner Mistakes Missing semicolon (;) at the end of a statement. Incorrect filename or file extension. Forgetting to include the necessary header files. Typing errors in commands or syntax. Summary Writing your first C program involves creating a file, adding basic syntax, compiling it, and running the executable. The "Hello, World!" program introduces key C concepts like functions, statements, and syntax structure. Attention to detail (like semicolons!) matters a lot in C. Learning Outcomes After this topic, you’ll be able to: Write and save a simple C program. Compile code using a C compiler like GCC. Execute your compiled program from the terminal. Troubleshoot basic syntax and compilation errors. Common Interview Questions Q1: What is the entry point of a C program?[Zoho]A: The main() function. Q2: What library must be included to use printf in C?[IBM]A: #include <stdio.h> Q3: What happens if you forget a semicolon in C?[Accenture]A: Compilation will fail with a syntax error. Q4: What does the return 0; statement do in C?[TCS]A: It signals successful program completion to the operating system. Practice Exercises & Quizzes Exercises Write a program that prints your name. Write a program that prints two lines of text. [quiz-cat id="20928"] Additional Resources Learn C Programming C Programming for Beginners - Udemy Course
