Wireless home security systems use radio waves to transmit their signals rather than wires. This has two advantages - first, they are easier to install than having to run wires throughout your house and second, there are no wires for a potential intruder to cut to bypass the system.

Wireless home security systems can be monitored or un-monitored. In a monitored system, a signal will be sent to a central monitoring station if the alarm is tripped and there may or may not be an audible alarm. With an un-monitored system an alarm will sound if the system is tripped, but nobody is informed of the alarm.

The "brains" behind a wireless security system is the control panel. This control panel is usually located somewhere out of the way like the basement or in a closet. It receives signals from the magnetic switches and motions sensors throughout the house and analyzes these signals to determine when to sound the alarm.

Magnetic switches are used on doors and windows and are composed of two pieces. There is a switch that gets mounted on the door or window and a magnet that mounts on the window- or door-frame. If the switch moves out of alignment with the magnet, it sets off the alarm.

Motion sensors are normally used in larger rooms or hallways. The use an infrared motion detector to sense movement or in some cases body heat. If they are tripped, a signal gets sent to the control panel which analyzes it to determine if it is a suspicious motion. This way it can filter out movement such as pets that roam freely.

A wireless alarm also includes a keypad that is used to control the system and arm or disarm it. The keypad is normally placed near the main entrance to the house.

Something to keep in mind with a wireless home alarm system is that each of the components is likely powered by battery. These batteries are normally long-life and should last for a number of years before having to be replaced.

They will have to be replaced however, and this is something to consider when choosing your alarm. Will you have to replace them yourself (or pay someone to do it) or is it included in the service contract from the alarm company?