The switch words are interpreted as opening and closing. It also refers to an electronic component that can make circuits open, interrupt current, or flow to other circuits. The most common switches are electromechanical devices that allow people to operate, with one or several electronic contacts. The "closed" (closed) of the contact indicates the electronic contact guide, allowing the current to flow through; The "open" (open) of the switch indicates that the electronic contact leads to the open circuit, which does not allow the current to flow through.