Introduction to C++

What is C++?

C++ got its start in the early 1980s. A Danish computer scientist named Bjarne Stroustrup was working with the C programming language but wanted to add features from another language he liked, Simula. The result was a new language he initially called "C with Classes."

By 1983, the name changed to C++. The "++" is a clever nod to the C language, where ++ is an operator that increments a value by one. C++ was designed to be a powerful, general-purpose language that gives programmers a high level of control over system resources and memory.

Getting Set Up

To start writing C++ programs, you need two key tools: a text editor and a compiler. The text editor is where you'll write your code. The compiler is a program that translates your C++ code into machine code, the language your computer's processor can understand.

Most developers use an Integrated Development Environment (IDE), which bundles a text editor, a compiler, and other helpful tools like a debugger. Popular IDEs for C++ include Visual Studio, Code::Blocks, and CLion. For beginners, Code::Blocks is a great free and open-source option that works on Windows, macOS, and Linux.

No matter which IDE you choose, the core process is the same: write code in the editor, compile it, and then run the resulting program.

Your First Program

It's a long-standing tradition in programming to make your first program in a new language simply display the phrase "Hello, World!" on the screen. Let's do that now.

Open your IDE or text editor and type the following code exactly as it appears here:

#include <iostream>

int main() {
    // This line prints "Hello, World!" to the console
    std::cout << "Hello, World!";
    return 0;
}

After typing the code, save the file with a .cpp extension, such as hello.cpp. Next, you'll need to compile it. In an IDE, this is usually done by clicking a "Build" or "Run" button. If you're using a command line, you would use a command like g++ hello.cpp -o hello.

Once compiled successfully, an executable file is created. Running this file will open a terminal or command prompt window and display your message.

Output: Hello, World!

Anatomy of a C++ Program

That small program introduces several core elements of C++ syntax. Let's break it down line by line.

#include <iostream>

This line is a preprocessor directive. It tells the compiler to include the contents of the iostream header file in our program. This file contains the code that allows us to get input and produce output, like printing text to the screen.

int main() { ... }

This defines the main function. A function is a block of code that performs a specific task. The main function is special; it's the entry point of every C++ program. When you run your program, the code inside the curly braces {} of main is what gets executed.

std::cout << "Hello, World!";

This is the statement that does the actual work. std::cout is the standard output stream, which usually means your screen. The << operator is used to send the text on its right to the stream on its left. Notice that the line ends with a semicolon ;. In C++, most statements must end with a semicolon. It's like the period at the end of a sentence.

return 0;

This line ends the main function. It sends a value of 0 back to the operating system, which is a standard way of saying that the program finished without any errors. This is the last thing our program does before it closes.

Let's check your understanding of these initial concepts.

Quiz Questions 1/5

Who is credited with creating the C++ programming language?

Quiz Questions 2/5

What is the primary function of a C++ compiler?

And that's your first step into C++. You've learned about its origins, how to set up your environment, and the basic structure of a program. From these simple building blocks, you can start creating much more complex and powerful applications.

C++ Mastery