Simon opines that even if there is an elaborate system of formal communication, it will always be supplemented by a complementary system of informal communication. In certain situations, information, advice and even orders flow along with informal channels. This informal network of communication is based on social relations within the organisation. In an organisation, two persons at different levels may be communicating with each other in a way not formally charted out. An informal condition of communication may be created by the social relations like friendship and competitiveness. The phenomenon of informal communication has been acknowledged as the “grapevine” that creates a system of relationships in an organisation, which is different from formal communication.
Simon observes, “The grapevine is valuable as a barometer of ‘public opinion’ in the organisation. If the administrator listens to it, it apprises him of the topics that are subjects of interest to organisation members; and their attitude toward these topics”. Many students, however, reveal that too much reliance on the informal channels may lead to the undermining of the system of formal communication in an organisation. In an organisation, there is a need for reliable data and information for decision-making, which is widely acknowledged. For this purpose, organisations are using sophisticated information system.
In which they make use of information and communication techno-logy, such as digital devices, web networks and upgraded computer systems. In communication system, designing information system has grown into a technical profession. An attempt to develop a systematic data leads to collection and storage of useful data, which is relevant to management. The information system in communication is not a mere technique, but it is useful in solving managerial problems.
Thus, data and information, which are necessary for decision-making, have to be organised and streamlined in an organisation, and for its proper supervision, adequate control processes are necessary.