Let's take this program as an example:

Code:
// This programs converts feet to metres or vice versa

#include <iostream>
using namespace std;

int main ()
{
    short userchoice;
    double metres;
    double feet;

    cout << "To convert feet to metres, please press 1\n";
    cout << "To convert metres to feet, please press 2\n";
    cin >> userchoice;
    cout << "\n";

    if (userchoice == 1)
    {
        cout << "Please enter the number of feet: ";
        cin >> feet;
        metres = feet/3.28;
        cout << feet << " feet = " << metres << " metres\n";
    }

    if (userchoice == 2)
    {
        cout << "Please enter the number of metres: ";
        cin >> metres;
        feet = metres*3.28;
        cout << metres << " metres = " << feet << " feet\n";
    }

    cout << "\n";
    system("PAUSE");
    return 0;
}
In this case, a pause is needed after displaying the result or else the program would instantly close without allowing the user to see it. Should I stick to 'system("PAUSE")' for simple programs?