Explore OOP in C++ to write cleaner, modular, and scalable code. Learn classes in C++, data hiding, encapsulation, abstraction, inheritance, and polymorphism in C++.

Become  a C++ Programmer

This module aims to teach us how to write cleaner, more modular, and scalable code in C++ by providing an understanding of OOP in C++. We'll start with the basics of object-oriented programming and build up to advanced concepts such as inheritance, data hiding, and polymorphism. Along the way, we'll explore how each concept applies to C++ and how various C++ features facilitate OOP.

Object-Oriented Programming in C++

## What is a Constructor?

As the name suggests, the constructor is used to *construct* the object of a class. It is a special member function that outlines the steps that are performed when an instance of a class is created in the program.

>A constructor's **name** must be exactly the **same** as the name of its class.

The constructor is a special function because it **does not have a return type**. We do not even need to write `void` as the return type. It is a good practice to declare/define it as the first member function.

So, let's study the different types of constructors and use them to create class objects.

## Default Constructor

The default constructor is the most basic form of a constructor. Think of it this way: 

> In a default constructor, we define the default values for the data members of the class. Hence, the constructor creates an object in which the data members are initialized to their default values.

This will make sense when we look at the code below. Here, we have a **Date** class, with its default constructor, and we'll create an object out of it in `main()`:



# What is a Constructor?

As the name suggests, the constructor is used to *construct* the object of a class. It is a special member function that outlines the steps that are performed when an instance of a class is created in the program.

>A constructor's **name** must be exactly the **same** as the name of its class.

The constructor is a special function because it **does not have a return type**. We do not even need to write `void` as the return type. It is a good practice to declare/define it as the first member function.

So, let's study the different types of constructors and use them to create class objects.

# Default Constructor

The default constructor is the most basic form of a constructor. Think of it this way: 

> In a default constructor, we define the default values for the data members of the class. Hence, the constructor creates an object in which the data members are initialized to their default values.

This will make sense when we look at the code below. Here, we have a **Date** class, with its default constructor, and we'll create an object out of it in `main()`:



In this lesson, we explore the world of constructors and learn why they are necessary for a class.

Introduction

Classes

Data Hiding

Inheritance

Polymorphism

Conclusion

Constructors

What is a Constructor?