Postfix and Prefix

What is difference between Postfix and Prefix Operators?

int n=0, m=0;  
n = ++m; /*first increment m, then assign its value to n*/  
cout << n << m; /* display 1 1*/

int n=0, m=0;  
n = m++; /*first assign m's value to n, then increment m*/  
cout << n << m; /*display 0 1*/