I have either a 3-way or a 4-way light switch that I want to replace with a dimmer switch of the same type. The existing switch has 4 conductors, does that mean it's a 4-way switch?
Technically the 4 way switch is the only type you need-- it can be wired in to the end points like a three way or even serve as an ordinary single on/off by not using some of the terminals. But they are a lot more expensive than the other types.