In the continuation of C++ programming, we will discuss about the Global Variables and the Local Variables. But first of all, let us understand what a variable is.

A variable is a name which acts as a storage location or container where different values can be manipulated.

Now we will discuss about Global Variables. Global Variables are the variables which are declared before the main function of the program. If we declare a variable globally, we can access it from any part of the program. They remain in memory throughout the runtime of the program. The values cannot be changed by any other function.

But in contrary to this, Local Variables are the variables which are declared in the main function of the program. The user can provide different values during the runtime of a program.

NB:
→ We can accept the values of a variable using the Insertion operator.
→ But we can also initialize the variable with a fix value, for example x = 10.

Good Software like wine, takes time
- Joel Spolsky

// Program to illustrate the Global and Local Variables declaration
#include<iostream>
using namespace std;
int glob; // this is global variable declaration
int main()
{
          int a = 8, b = 2; // this is local variable declaration
          glob = a + b;
          cout<< glob;
          return 0;
}

10   

#include<iostream>
using namespace std;
int glo = 6;
void sum()
{
     int a;
     cout << glo;
}  
int main()
{
     int glo = 10;
     glo = 121;
     int a = 10, b = 5;
     float pi = 3.14;
     char c = 'y';
     bool t = true;
     sum();
     cout << glo << endl << true << endl;
     cout << "\nHere the value of a is " << a << "\nThe value of b is " << b;
     cout << "\nThe value of pi is " << pi;
     cout << "\nThe value of c is " << c;
     getch();
     return 0;
}