Introduction to C++

C++ is a general-purpose programming language developed by Bjarne Stroustrup as an extension of C. It is widely used for developing high-performance applications, system software, games, and embedded systems.

• Supports both procedural and object-oriented programming paradigms.
• Provides fast execution speed and direct memory management capabilities.
• Widely used in operating systems, game engines, embedded systems, and competitive programming.

First C++ Program

The below C++ code shows the basic structure of a program.

#include <iostream>
using namespace std;

int main() {
    cout << "Hello, World!";
    return 0;
}

Hello, World!

Structure of the C++ program

The basic structure of a C++ program defines the standard way every program must be written; otherwise, it will cause a compilation error. The structure includes:

• Header File: #include <iostream> adds input/output objects (cin, cout, etc.) via the preprocessor. Common headers: fstream (files), string (strings), vector (STL), bits/stdc++.h (all-in-one).
• Namespace Declaration: using namespace std; allows direct use of standard names like "cout" without std::
• Main Function: int main() is the program’s entry point; execution starts here and returns an integer with return 0 mean successful execution.
• Comments: // for single line, /*....*/ for multi-line are ignored by the compiler and used only for code documentation.
• Statement: Contains executable code. Here, cout << "Hello World!", prints the text on the screen using the insertion operator (<<).
• Return: The return 0; statement terminates the main() function and indicates that the program executed successfully.

How to Run the Above Code?

• Write the code in a file such as HelloWorld.cpp.
• Use a C++ compiler (G++, Clang, or MSVC) to compile the source code.
• The compiler converts the source code into an executable file (such as HelloWorld.exe).
• The operating system loads the executable file into memory.
• The CPU executes the program instructions starting from the main() function.
• The program displays the output on the screen.

Related Article

• History of C++
• Features of C++
• C++ vs Other Languages