What is the function of an N.O. switch in a circuit?

The function of a normally open (N.O.) switch in a circuit is to complete the circuit when activated. When the switch is in its default state, it remains open, meaning that there is a break in the circuit and current cannot flow. When the switch is activated, it closes the circuit, allowing electricity to flow through. This operation is essential in various applications, such as in control systems, where pressing a button or flipping a switch initiates an action by allowing current to pass, thereby completing the circuit needed for the subsequent operation of devices like motors or lights. The design inherently relies on the switch remaining open until manual or automatic activation occurs, showcasing its key role in controlling the flow of electricity in a system.