What is the difference between a closed-loop and an open-loop system?

The correct answer highlights a fundamental distinction between closed-loop and open-loop systems based on the presence of feedback.

In a closed-loop system, feedback is essential as it continuously monitors and adjusts the system's operation in response to the output. This feedback allows for real-time modifications that help maintain desired performance levels or conditions. In practical terms, closed-loop systems can self-correct, which increases their accuracy and reliability. For example, a thermostat in a heating system is a closed-loop system; it measures the temperature of the environment and adjusts the heating accordingly.

Conversely, open-loop systems operate without any feedback mechanism. They execute a predetermined action based on initial input without monitoring the outcome. These systems do not adjust based on the results of their actions, which can lead to a lack of precision in achieving the desired effect. For example, a basic timer-controlled sprinkler system is an open-loop system; it runs for a set time regardless of whether the lawn has been adequately watered.

Understanding this difference is crucial in engineering and control system design since it directly influences how systems are monitored, controlled, and optimized for specific applications.