Exchange of information through the use of speech, signs or symbols is called communication. When early humans started speaking, some 5,00,000 years ago, that was the first mode of communication. Communication over a long distance when people who are communicating are not in direct line of each other’s site is called telecommunication. Invention of telephone and establishment of commercial telephony in 1878 marked a turnaround in communication systems and real telecommunication was born. Telephones slowly gave way to television, videophone, satellite and finally computer networks. Computer networks have revolutionized modern day communication and communication technologies.