Computer Network Definition: The interconnected group of computer which helps in the transfer of data/information through transmission media and computer technologies is known as computer network. Data comunication: The transferring of digital data or information among computers through computer network is known as data communication. sending and recieving emails,IRC and transferring files etc are data communication. Telecommunication: It is the exchange of information over significant distances by electronic means like telephones,radio,TV,computers,mobile phones etc. Simplex transmission mode: Communication which takes place in only one direction (i.e. transmission of data).Radios and televisions are simplex. In half duplex transmission mode: Data can be transmitted in both directions, but in only one direction at a time. Walkie talkie is half duplex. Full Duplex: The device which can transmits data in both the directions at a time.The transmission ...