Which system uses feedback from the output to control its input?

A closed loop system is one that utilizes feedback from its output to adjust and control its input. This means that it continually monitors the output and makes necessary adjustments to ensure the output remains within desired parameters. This feedback mechanism allows for self-regulation and helps maintain stability and accuracy in a wide range of applications, from simple thermostats to complex automated processes.

In contrast, an open loop system does not use feedback; it operates solely based on predetermined inputs without correcting for any deviations in output. Feedback systems can be synonymous with closed loop systems, but the term "closed loop system" specifically describes the nature of utilizing feedback effectively for control. An input control system does not inherently imply the use of feedback from the output, which is essential for the definition of a closed loop system. Thus, the closed loop system is the precise term that encompasses the idea of feedback-driven control.