A rocker switch is an on/off switch that rocks (rather than trips) when pressed, which means one side of the switch is raised while the other side is depressed much like a rocking horse rocks back and forth. A rocker switch may have a circle (for "on") on one end and a horizontal dash or line (for "off") on the other to let the user known if the device is on or off. Rocker switches are used in surge protectors, display monitors, computer power supplies, and many other devices and applications.
A rocker switch with independent circuitry can have a light activated on the face of the switch in both the on and off positions, which allows the switch to be found easily in the dark. With dependent circuitry, the light is activated only when the switch is on.