What's a Three Way Light Switch?

A 3-way switch is larger than a single pole switch and has three screw terminals for wiring connections, plus a ground. Two of these take traveler wires that go from one switch to the other. For the third terminal, one switch is connected to the hot supply wire while the other switch is joined to the light.

What is the difference between a 2 way and 3 way switch?

2 Way Switches have 3 screws, whereas 3 Way Switches have 4 screws. But irrespective of that, in both cases, you can employ 2 switches to control the load. You need to use 2-wired cable both between the switches and between the light fitting and a switch for 2 Way Switching.

When should you use a 3 way switch?

Three-way switches are commonly used to control a light fixture from two different locations. For example, a long hallway or stairway might use a pair of three-way switches at each end so that lights can be turned on when approaching one end of the hall or stairway, then shut off from the other end.