Our requirements force us to find ways of getting it. In the olden days when man felt the need of protection from wild beasts and cold, he invented fire by striking two pieces of stone. Slowly and slowly with the marching of time many developments took place in man’s life. He started thinking of comfortable life. For his comforts sewing machine, radio, TV, trains, ships and aeroplanes were invented. As the man grew up, modernization of living standard took place and to satisfy the need of his living standard many new things came into existence. Computer, internet, cellular phone and many things in telecommunication were invented. So it is always right to say that necessity is the mother of invention.