👉 Controllable is a concept in control theory, which refers to a system that can be directly or indirectly controlled by external inputs. This means that the system can be made to operate under certain conditions, but it requires specific input signals to achieve this effect. In other words, if you provide the right input signal, the system will respond and perform the desired action. For example, a motor controller may control the speed of an engine based on the input voltage, while a thermostat adjusts the temperature in your