🟣 OOP · Lesson 42

Access Specifiers: public, private, protected

What is Access Specifiers: public, private, protected?

Access Specifiers: public, private, protected
Access specifiers control visibility of class members. They protect data and support encapsulation.

Level
🟣 Object-Oriented Programming

Example File
access-specifiers.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
public	Access Specifiers: public, private, protected programming में Public use होता है।
private	Access Specifiers: public, private, protected programming में Private use होता है।
protected	Access Specifiers: public, private, protected programming में Protected use होता है।
encapsulation	Access Specifiers: public, private, protected programming में Encapsulation use होता है।
visibility	Access Specifiers: public, private, protected programming में Visibility use होता है।

Syntax / Pattern

C++

private members are accessed through public methods.

Example Program

main.cpp

#include <iostream>
using namespace std;
class Student{
private:
    int marks;
public:
    void setMarks(int m){ marks = m; }
    int getMarks(){ return marks; }
};
int main(){ Student s; s.setMarks(91); cout << s.getMarks(); }

Expected Output

Program Explanation

marks is private, so it cannot be accessed directly outside class.
Public methods provide controlled access.

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?

secure data models
validation
clean class design

Common Mistakes

Making all members public.
Trying to access private data directly.

Practice Tasks

Create private balance and public deposit method.
Differentiate public/private/protected.

Summary

Access Specifiers: public, private, protected एक ज़रूरी C++ topic है। परिभाषा सीखें, syntax समझें, example program चलाएं और फिर practice tasks हल करके concept मज़बूत करें।