Stop walking across a dark room to turn on the light. Install a 3-way switch and control lights from two locations.

switch rocker mechanism to open or close a circuit commonly used in power strips and appliances Photo and symbol for single pole, double throw (SPDT) toggle switch single pole double throw (SPDT ...

Unlike single-pole switches, which control lights from one location, 3-ways work in pairs. You must have two of them — and only two. (For more than two locations, add 4-way switches.) ...