Data communication is used for transfer of data from one device to other via some form of transmission media.
The exchange of data between two devices via some form of transmission medium such as cable wire. For data communications to occur, the communicating devices must be part of a communication system made up of combination of hardware (physical equipments) and software (programs).
Data communications refers to the transmission of this digital data between two or more computers and a computer network or data network is a telecommunications network that allows computers to exchange data.
Data communication is the transmission of digital messages to external devices. If you look around your house, you will see many examples of data communication at work. Your cable system, your home phone and even your computer all work based on varying types of data transfer.
Data transmission refers to the process of transferring data between two or more digital devices. Data is transmitted from one device to another in analog or digital format. Basically, data transmission enables devices or components within devices to speak to each other.