Automatic Control and System Theory 1

System is a structure that consists of interrelated and interdependent elements, which influence one another to maintain their working and the existence of the system, in order to achieve the goal of the system. All systems have input, output and feedback in order to maintain an internal steady-state even if external environment tends to change. System is generally used in many sectors, like process control, data elaboration, biology, economy, ecology, management, traffic control, etc.