Or in other words if you're used to seeing switches from the electronics side of the world:
2 way: SPST
3 way: SPDT
4 way: DPDT
I once lived in a house with a 5(!) gang box with three of the switches wired to the upstairs hall light incorrectly and another switch upstairs. It was as big a mess as you'd imagine.
2 way: SPST
3 way: SPDT
4 way: DPDT
I once lived in a house with a 5(!) gang box with three of the switches wired to the upstairs hall light incorrectly and another switch upstairs. It was as big a mess as you'd imagine.