To put it simply, the transfer of data from a source to a destination can be defined as data communication. In data communication, one is only interested in how the data is transferred, that is the method or the channel used for transmitting the data to the receiver, and not really on how the data is generated or how it is going to be used.
Data communication basically involves three elements - the sender or source, the channel or the medium and the receiver or the destination. Absence of any one of these elements will not make data communication successful. The sender or the receiver can be employees within the same organization or from different organizations from different parts of the world.
Data communication can happen over different channels, the most popular being telecommunications and the internet. The method used for communication of data usually depends on a number of factors like the nature of data, the urgency of delivering it, and the intention behind that communication.
For example, a business can depend on the internet or the intranet networks, and not on telecommunications, to send important communication like notices, announcements, memos etc to all its employees.
In an organization, data communication is usually facilitated with the help of LAN or Local Area Networks. The LAN connects the systems within the organization via cables and virtual networks, and enables sharing of information between them. The internet, on the other hand, enables you to transfer data from a source to any destination, anywhere in the world.
Irrespective of languages, the operating systems, type of network and location of the computer, the data communications protocols make not possible to transfer and share information with numerous other computers. | 
