Introduction

When students start learning C programming, one of the first questions they have is:
Where do we write a C program and how does it run?

Before learning syntax or writing code, it is important to understand the environment used for writing and executing C programs.
This blog explains the basic tools and steps involved in running a C program, in a simple way for first-year engineering students.

Where Do We Write a C Program?

A C program is written in a text editor or an Integrated Development Environment (IDE).

1️⃣ Text Editor

A text editor is a simple software used to write program instructions as text.

Examples:

• Notepad (Windows)

• Notepad++

• VS Code (used as editor)

• Vim (Linux)

These editors are used only to write and save the program.

📌 The C program is saved with .c extension.

What Is an IDE?

An IDE (Integrated Development Environment) is software that provides:

• Text editor

• Compiler

• Error messages

• Output window

All in one place, making it easier for beginners.

Examples of IDEs:

• Code::Blocks

• Dev-C++

• Turbo C (older)

Using an IDE reduces manual work and helps students focus on learning.

What Is a Compiler?

The computer cannot understand C language directly.
A compiler is software that converts a C program into machine language.

Examples of C compilers:

• GCC (GNU Compiler Collection)

• Turbo C compiler

The compiler:

• Checks errors in the program

• Converts it into executable form

The execution of a C program happens in the following steps:

1️⃣ Writing the program
The program is written in a text editor or IDE.

2️⃣ Saving the program
The program is saved with .c extension.

3️⃣ Compilation
The compiler checks the program and converts it into machine code.

4️⃣ Execution
The executable file is run to get the output.

📌 If errors are present, the program will not execute until they are corrected.

How to Run a C Program Using VS Code

Step 1: Install Required Software

Before running a C program in VS Code, two things are required:

1️⃣ VS Code (Code Editor)
2️⃣ C Compiler (such as GCC)

📌 VS Code is used to write code
📌 Compiler is used to convert code into machine language

Step 2: Open VS Code

• Launch VS Code

• You will see the editor window

Step 3: Create a C Program File

• Click File → New File

• Save the file with .c extension
  Example: program.c

📌 .c extension tells the system that this is a C program.

Step 4: Write the C Program

• Write your C program in the editor

• Save the file (Ctrl + S)

Step 5: Open the Terminal in VS Code

• Click on Terminal → New Terminal

• A terminal window will open at the bottom

Step 6: Compile the C Program

In the terminal, type the compile command:

gcc program.c

• his checks for errors

• If there are no errors, an executable file is created

📌 If errors appear, the program will not run until they are corrected.

Step 7: Run the Program

To execute the program:

a or a.exe

The output will appear in the terminal window.

Step 8: View Output

• The program output is displayed in the terminal

• Input (if required) is also given through the terminal