Object-oriented programming is a software design methodology that uses classes and objects, simplifying development and maintenance. A class acts as a blueprint for creating objects, which are real-time entities representing various items. The document also explains access modifiers (private, default, protected, public) that control the visibility of class members.

1. OBJECT ORIENTED
PROGRAMMING

2. OBJECT ORIENTED PROGRAMMING
• Object-Oriented Programming is a methodology or
paradigm to design a program using classes and objects.
It simplifies the software development and maintenance
by providing some concepts defined below :
• Classes
• Objects

3. Class
• Class is a user-defined data type which defines its
properties and its functions. Class is the only logical
representation of the data.
• For example, Human being is a class. The body parts of
a human being are its properties, and the actions
performed by the body parts are known as functions.
• The class does not occupy any memory space till the time
an object is instantiated.

4. Object
• Object is a run-time entity.
• It is an instance of the class. An object can represent a
person, place or any other item.
• An object can operate on both data members and
member functions.

5. Code example of class
Class Room{
Public:
double length;
double breadth;
double height;
double calculate area()
{
return length*breadth;
}
double calculate volume()
{
return length*breadth*height;
}
}

6. Code example of object
• int main() {
• // Creating an instance of the Room class
• Room myRoom;
•
• // Setting the attributes
• myRoom.length = 10.0;
• myRoom.breadth = 12.0;
• myRoom.height = 8.0;
•
• // Calculating and displaying the area
• double area = myRoom.calculate_area();
• cout << "The area of the room is: " << area << " square units“;
•
• // Calculating and displaying the volume
• double volume = myRoom.calculate_volume();
• cout << "The volume of the room is: " << volume << " cubic units" ;
•
• return 0;
• }

7. Access specifier
• Private: The access level of a private modifier is only within
the class. It cannot be accessed from outside the class.
• Default: The access level of a default modifier is only within
the package. It cannot be accessed from outside the
package. If you do not specify any access level, it will be the
default.
• Protected: The access level of a protected modifier is within
the package and outside the package through child class. If
you do not make the child class, it cannot be accessed from
outside the package.
• Public: The access level of a public modifier is everywhere.
It can be accessed from within the class, outside the class,
within the package and outside the package.