How a home security system with motion detector works?

Please provide me wiht information about home security system and how they work ?

Public Comments

1. google has the answers you seek
2. this is not a smart answer but our chow dog does this chore very well. we are very seldom troubled by prowlers or intruders of any kind think about it
3. Check out http://ucontrol.com. A lot of good info about alarm systems on that site.