Two wires called “travelers” connect the first switch to the second one. Then power leaves the second switch to go to the light. No matter which switch you flip, the light responds.

I always connect wires in the same order ... Turning off a switch cuts power to the light or whatever the switch controls, ...

So why not play it safe and make use of your light switch? Admittedly, it wasn’t because [Tyler Bletsch] didn’t want to mess around with AC directly, but rather out of necessity. You see ...

Smart light switches usually connect to your internet via Wi-Fi, Z-Wave, or Zigbee. Through Wi-Fi, your switch links to your router, whereas Z-Wave and Zigbee use smart home hubs.