🟣 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	Public used in Access Specifiers: public, private, protected programming.
private	Private used in Access Specifiers: public, private, protected programming.
protected	Protected used in Access Specifiers: public, private, protected programming.
encapsulation	Encapsulation used in Access Specifiers: public, private, protected programming.
visibility	Visibility used in Access Specifiers: public, private, protected programming.

Syntax / Pattern

private members are accessed through public methods.

Example Program

#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 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.