Today¿s Computer networks have been the effect of progress from few decades ago. The invention of computer networks has its own history of evolution and started setting up their milestones day by day. The reason behind caring the communication is greatly evident, if no communication then world is filled of silence.The evolution of computer networks will offer you the deeper understanding of the greater achievements in this era. The computer networks weave their path to emerge from late 1960s. After the long way with the technological developments, in the mid-1990s, the growth of the Internet is enormous and written communication becomes vital in every individuals life. The influence of computer networks on other telecommunication network is known as ¿network convergence¿. Prior to digital evolution, the telephonic conversation is an analog mode of signal transmission. Digital voice transmission on the telephone network is one of the best and first signs to speak out the speciality of ¿convergence¿. The new services in computer networks are the prerogatives of telephone, radio and Television services.