Control System: If the output is of our desire and able to control, then the system is called as Control systems
When the output quantity of the control system is not fed back to the input quantity, the control system is called an Open loop System. e.g. Blind man's action, traffic control without traffic police
2. Closed loop System: In the Closed loop Control System the control action is dependent on the desired output, where the output quantity is considerably controlled by sending a command signal to input quantity. The closed loop systems are normally have feed back.
e.g Normal man's action, Automobile systems, traffic signal control with traffic police etc.
Based on the type of system, control systems can be classified as
2. Mechanical System (Translational, Rotational)
3. Hydraulic system
4. Pneumatic systems
5. Thermal systems and so on.