The means by which information is conveyed from one place to another or from one operation to another is called communication. The word communication goes beyond of the word speaking and writing and it includes all aspects of verbal, unspoken and unwritten communication.

When the information flows from the top management to the lower management, it is a case of downward communication. The internal communication from the superior to the subordinate is termed as downward communication and it includes
orders, instructions and notices issued to subordinates.

The flow of information from the subordinate to the superior manager is called upward communication. The upward communication covers suggestions, grievances, complaints and reports.