Difference between Base class and Derived class in C++

Base Class: A base class is a class in Object-Oriented Programming language, from which other classes are derived. The class which inherits the base class has all members of a base class as well as can also have some additional properties. The Base class members and member functions are inherited to Object of the derived class. A base class is also called parent class or superclass.
Derived Class: A class that is created from an existing class. The derived class inherits all members and member functions of a base class. The derived class can have more functionality with respect to the Base class and can easily access the Base class. A Derived class is also called a child class or subclass.
Syntax for creating Derive Class: 
 

class BaseClass{
  // members....
  // member function 
}
     
class DerivedClass : public BaseClass{
  // members....
  // member function 
}

Difference between Base Class and Derived Class:
 

Below is the program to illustrate Base Class and Derived Class:
 

// C++ program to illustrate
// Base & Derived Class

#include <iostream>
using namespace std;

// Declare Base Class
class Base {
public:
    int a;
};

// Declare Derived Class
class Derived : public Base {
public:
    int b;
};

// Driver Code
int main()
{
    // Initialise a Derived class geeks
    Derived geeks;

    // Assign value to Derived class variable
    geeks.b = 3;

    // Assign value to Base class variable
    // via derived class
    geeks.a = 4;

    cout << "Value from derived class: "
         << geeks.b << endl;

    cout << "Value from base class: "
         << geeks.a << endl;

    return 0;
}

Value from derived class: 3
Value from base class: 4