As you walk into your home, the convenience of switches light the rooms of your home. They complete the circuit to your light fixtures when you turn the switch on to light the light and they break the circuit when you turn off the switch to turn the light off.
Single-pole switches are the most basic switches. They simply turn a light on and off. They come in a variety of colors and are rated for 15 and 20 amps.
Three-way switches control lights from two different locations. By adding a four-way switch between them, you can control lighting from three locations. Common uses for three-way switches are hallways, stairwells, or large rooms like living rooms with more than one doorway in them.
Dimmers switches control a lights brightness or intensity. These switches use rheostats to brighten or dim the lights and are a glorified single-pole switch with options. Dimmer switches often replace single-pole switches in homes. These switches work just fine with incandescent lighting, but specialized dimmer switches are required for ceiling fans and fluorescent lights.