1. You set a desired temperature. When it is below the desired temperature, your area gets warmer. When it is above your desired temperature, your area gets cooler. How does this system work?
  2. You put some food in a microwave oven and set a power and time, and then push start. What kind of feedback loop is this?
  3. As you walk towards some automatic doors, a sensor sends a signal to an actuator which then opens the door. Do the doors open more quickly if you are walking quickly towards them?
  4. You use GPS to get your position.How does GPS work?

All the example above are control systems. There is usually a sensor, a micro-controller, and an actuator that come together to produce a desired behavior.