Successful feedback control of small systems allows for the rectification of thermal fluctuations. converting them into useful energy; however. control itself requires work. This paper emphasizes the fact that the controller is a physical entity interacting with the feedback-controlled system. https://www.bekindtopets.com/great-deal-Sophie-Allport-Bee-Blackout-Ready-Made-Eyelet-Curtains-Duck-Egg-big-savings/