A:Answer Not incompatible. Normal wiring is three wires - black, white, and copper. The black is the "hot" wire, the white is the neutral, and the copper is the ground. When you put a switch in a circuit you now have 6 wires - three coming in and three going out. Since the switch cuts the power on and off, there will be a black wire coming into the switch and a black wire leaving. The whites are normally just connected together with a wire nut and the coppers are connected together with a wire nut or grounded to a metal junction box.
So the new switch has four wires. Follow the directions. The white gets connected to the other two whites, The black gets connected to the incoming black. The blue gets connected to the outgoing black, The ground (green?) gets connected to the other two coppers or just taped off. Follow the directions.
It is important to connect the switch's black wire to the INCOMING house black so that the switch has power to run the circuitry in the switch.
Hope that helps. If you don't understand, call an electrician.