Control devices are tools or systems that help manage and regulate the operation of machines or processes. They can be simple, like a light switch that turns a lamp on and off, or complex, like a computer program that controls an entire manufacturing line. These devices ensure that everything runs smoothly and efficiently, making our lives easier and safer. In many cases, control devices use sensors to gather information about their environment. For example, a thermostat monitors the temperature in a room and adjusts the heating or cooling system accordingly. This feedback loop allows for precise control, helping to maintain desired conditions and improve energy efficiency.