🟣 OOP · Lesson 38

Classes and Objects

What is Classes and Objects?

Classes and Objects
A class is a blueprint and an object is an instance created from that blueprint. Classes combine data members and member functions.

Level
🟣 Object-Oriented Programming

Example File
classes-objects.cpp

Main Focus
Concept + syntax + practical C++ program

Why should you learn this?

It helps you write correct and readable C++ programs.
It is used repeatedly in school practicals, projects and competitive programming.
It builds the base for advanced topics such as OOP, STL and data structures.

Important Terms

Term	Meaning / Use
class	Class used in Classes and Objects programming.
object	Object used in Classes and Objects programming.
data member	Data member used in Classes and Objects programming.
member function	Member function used in Classes and Objects programming.
instance	Instance used in Classes and Objects programming.

Syntax / Pattern

class ClassName { members; }; ClassName obj;

Example Program

#include <iostream>
using namespace std;
class Account{
public:
    int balance = 5000;
    void show(){ cout << balance; }
};
int main(){
    Account a;
    a.show();
    return 0;
}

Expected Output

5000

Program Explanation

Account defines structure and behavior.
a is an object of Account.

Exam Tip: In C++ practical answers, write the logic first, then the program, then expected output. For theory, always include one suitable example.

Where will you use it?

bank account
student profile
product record

Common Mistakes

Forgetting semicolon after class.
Calling non-static member without object.

Practice Tasks

Create class Student with roll and name.
Create two objects and print data.

Summary

Classes and Objects is an important C++ topic. Learn the definition, understand the syntax, run the example program and then solve the practice tasks to make the concept strong.