In the old time (you know before...), we were used to rely on area code in order to locate people thanks to their phone number. For instance, I remenber that instead of learning my parents' complete phone number, I just learn the four last digits : 11 43 because all the others were the same for the locality. An at the time, I did not anybody outside my country I did not learn my international code as well. And the numbers evolved : +33 4 77 60 11 43 33 is the international 2 digit 4 is because my parents live in the fourth quadrant of france 77 is the code for the department 'La Loire' 60 is the code for our city -> I just learnt the 11 43

Now we don't have to learn, the cell phone has a memory, we could just notice the fact that the ultimate area code is the one devoted to phone numbers : in france it is 06 13 or 06 14, in switzerland it is 078 or 079. Those number are connected to the virtual realm of cell phones...