All of us were limited to making and receiving calls only from the fixed phones till a couple of years back. 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 mobile phones arrival has changed all that. Phone calls can now be made from anywhere unless and until there is a signal jammer in the locality.