A few years ago, all of us were restricted to making and receiving calls only from the fixed phones. It is true that wireless handsets were also there, but their range was just within a hundred meters or so from the base station. If we wanted to make any emergency calls while on the move, we had no other option apart from getting down somewhere and initiating our call from there. The advent of the mobile phones has changed all that. Unless and until there is a signal jammer in the locality people can now make phone calls from anywhere they want.