Open loop
When a control system is open loop, it means that there is no feedback mechanism. The input and the controller doesn't know what's happening on the output. This typically yields a much simpler, less expensive system but one that is completely inflexible and is more likely to have inconsistent outputs.
In an open-loop controller, also called a non-feedback controller, the control action from the controller is independent of the "process output", which is the process variable that is being controlled.