Coded rotary switches are a type of switch that consists of a round or cylindrical shaft with multiple positions or settings, each of which is controlled by an internal coded disc or cam. When the shaft is turned to the desired position, it activates the coded disc to activate a circuit. The code can be a combination of letters, numbers, or symbols. These switches are generally used for controlling electrical circuits, and its code can tell the user which position the switch is in. Coded rotary switches are very reliable, easy to use, and can be used for a variety of applications, such as controlling lighting, controlling ventilation systems, and more. They are also very durable and can be used for processes that require frequent switching.