The document provides an overview of various communication systems used in mines including:
1. Centralized control rooms that monitor equipment using fiber optic connections and video cameras to increase safety and productivity.
2. Telephone, radio, and wireless systems for person-to-person communication.
3. Remote control systems for person-to-machine communication like blast initiation.
4. Automatic systems like conveyor tracking and truck dispatch for machine-to-machine communication.
5. Data from these systems is stored centrally and analyzed to manage operations and make informed decisions through a management information system.