Switches open and close electrical circuits, allowing power to flow through lights and appliances. In recent years, there has been something of a Renaissance in light switches.

New switches offer a wide range of control, such as full-range dimming, a delayed fade from on to off, and dimmer switches that remember a range of different pre-set settings.

Some switches automatically turn lights on when a person is in a room, and central lighting controls can operate lights anywhere in the house.

You can also control lights with hand-held, infrared, wireless remotes.

Some switches are operated with keys, timers or photoelectric eyes that sense daylight. Some switches are paired up with electrical outlets (a "combination" switch) and others have a pilot light that lights when the switch is on.

Outdoor switches, mounted in a special box, are operated with a lever. Special dimmers are needed for fluorescent and neon lights and loads greater than 1000 watts.

Switches should match the amp and voltage ratings for the circuit. And if your home has aluminum wiring, be sure the switches are designated "CU-AL" for compatibility.

The most familiar light switch, the common "light switch" is actually referred to by hardware dealers and electricians as a "single pole switch."

With a single-pole light switch, the simplest and most common type, flipping the lever up completes the circuit, turning lights or appliances on and flipping it down breaks the circuit, turning lights or receptacles off.

A single pole switch has two brass terminal screws on the side.

The type of switch that will operate hallway lights from either end of the hallway is called a three-way switch.